A teenager trying to rescue his mother was killed in a flooded Rockville apartment building Wednesday, and a tornado touched down in the Annapolis area as the potent remains of Ida slammed the Washington region with wind, rain and flying debris.

Video posted on Twitter showed images of a funnel cloud along with airborne objects, the sound of thunder and downed utility poles along a wrecked section of West Street in Annapolis.

“Well guys, my building just got hit by a tornado,” Annapolis resident Taylor Fields tweeted shortly before 3 p.m. “I’m okay, but I’ve never heard anything like it.”

Tracy Cook, who also lives in Annapolis, said she was returning home from running errands when she saw the dark funnel moving through the city. She took shelter at the Annapolis Town Center as debris flew through the air.

“Frightening,” she wrote in a message. “Praying no one was hurt.”

Anne Arundel County Fire Department, which is investigating storm damage in the Annapolis and Edgewater area, tweeted Wednesday afternoon that there were no reports of injuries at this point.

Chris Trumbauer, a spokesman for Anne Arundel County, said he received an alert on his phone and went to the window outside his downtown Annapolis office.

“It was swirling clouds off towards Parole about a couple of miles away,” he said. “And now it turns out that’s where most of the damage was.”

A person in Edgewater, outside Annapolis, tweeted video of a gray twister swirling in the distance. A woman can be heard yelling: “You think it’s coming this way?”

A tornado moved through parts of Anne Arundel County, Md., on Sept. 1 as part of storms caused by remnants of Hurricane Ida. (The Washington Post)

At least one school in the area was severely damaged, according to pictures posted on Twitter.

In Rockville, the deceased was identified by family members as Melkin Cedillo, 19, who died when he returned to a flooded apartment to find his mother, whom he did not see outside. His mom, Daysi Cedillo, was able to escape but did not say when or how she made it out, family members said. A second person from the same apartment complex was unaccounted for as of 1 p.m., officials said.

More than 5,000 customers in the region were without power, and dozens of roads were closed because of floodwaters.

Rising water on the Potomac River threatened the historic downtown of Harpers Ferry, a chronic target for flooding where the Shenandoah River flows into the Potomac, the National Park Service said.

In Frederick County, a group of children reportedly had to be rescued from a school bus stranded on a bridge by high water.

The storm spread across much of the Mid-Atlantic. A tornado warning was issued in Philadelphia about 5 p.m., and tornado watches were posted along the easternmost section of the Pennsylvania turnpike, according to the Capital Weather Gang. Central Pennsylvania was getting several inches of rain. New York City was forecast to get heavy downpours and flash flooding, eight weeks after flash-flood waters poured into its subway system. The rain was so extreme that for the first time ever, the city was placed under a flash flood emergency, the flood alert for the most dire rainfall situations. Tornado watches were posted as far north as New London, Conn.

In Rockville, floodwaters rushed into Rock Creek Woods Apartments shortly before 4 a.m., according to Montgomery County police and fire officials.

The deluge trapped people in their apartments and water rose almost to the ceilings in some cases, officials said. Rescue crews got desperate calls from residents, pleading, “I can’t get out. … Come save me,” authorities said.

Some people had to be pulled out through their windows.

Three people were hospitalized for injuries that were not life-threatening, and one firefighter suffered minor injuries.

The deceased victim was found just outside one of the apartment buildings, said Montgomery County Fire Battalion Chief Daniel Ogren.

Family members said Cedillo lived in the complex with his family.

The family was asleep early Wednesday morning when they were awakened by rushing water rapidly filling their apartment.

Melkin Cedillo; his mother, Daysi Cedillo; and other family members, including a cousin, her husband and two young children — a baby boy and a 9-year-old girl — were all inside, according to Marta Cedillo, a family member. She spoke on behalf of her sister, the cousin inside the home, as she stood across the street from the building on Wednesday.

All got out safely. But when Melkin missed his mother, who was not standing with the rest of the family, he went back to the apartment to look for her, Marta Cedillo said.

“He never came back,” she said.

Iris Cedillo, another family member, said officials later told the family that they had found Melkin and he was dead.

He was found outside in about five feet of water, officials said.

The two children were taken to a hospital for treatment after they had swallowed a significant amount of water, Iris Cedillo said.

The apartment complex is made up of about 60 units, Ogren said.

About 12 of the units are at a walk-down terrace level. Early Wednesday morning — sometime after 3 a.m. — the area around the apartment buildings received a dump of about three inches of water in 45 minutes, Ogren said.

The apartment buildings sit in a “bowl,” but in the past have been kept relatively dry during flash floods by drains in the area, he said.

“We do not know if the drains became clogged, if they were simply overrun, or a combination,” he said.

Starting about 3:50 a.m., residents of the apartments started calling 911. Many had been asleep when the water rushed in.

“By the time they realized what was going on, they couldn’t get their doors open,” he said. “There was water in their apartment and outside the hallways.”

“I’m sure these people were absolutely terrified,” he said.

Firefighters steered rescue boats to the terrace-level apartments. They broke windows and pulled people out. Other firefighters entered the apartments by busting through the doors and even breaking through the ceiling from the floor above.

About 12 to 15 residents were rescued.

“Some of these people may have perished if we didn’t get them out,” Ogren said.

Water was pumped out of the apartments and the area around them, allowing rescuers to search the apartments.

No victims were found in the apartments.

Officials said about 150 people were displaced from the four apartment buildings, which are near Veirs Mill Road and Twinbrook Parkway.

They were transported by bus to the Mid-County Community Recreation Center in Silver Spring, where they were being provided relief and shelter by the American Red Cross and Montgomery County Health and Human Services.

The Moran family, who was living on the second floor of the flooded apartment building, arrived at the recreation center Wednesday afternoon.

Evelyn Moran, 14, said she woke up to thunder and lightning around 3 a.m. but thought it was going to be “a normal storm, like any other.”

Then she said she heard people outside yelling, “It’s flooding! It’s flooding!”

Her family grabbed some essential items and fled.

“We weren’t expecting this because none of this really happens where we live,” Moran said. “For us to be thrown into a situation like that is just kind of nerve-racking and also just kind of confusing because we don’t exactly know how to process it. It all just moved too quickly.”

Elsewhere, in Northern Virginia, more than 3,600 customers of Dominion Energy — mainly in the Tysons, Arlington and Springfield areas — were without power early Wednesday. Pepco said about 1,200 of its customers — mainly in the Petworth neighborhood in Northwest Washington and Hyattsville in Maryland — lost power.

Dozens of roads were closed because of downed trees and flooding.

In Fairfax County, police said more than a half-dozen roads were closed because of high water. Most of the closures in the Fairfax area were in McLean, Mount Vernon and Reston. At one point, the northbound ramp of the George Washington Parkway to the Capital Beltway was closed because of a downed tree.

Virginia State Police said they helped with heavily flooded roads and a “search and recovery” in hard-hit areas of Buchanan and Hurley.

In Maryland, flooding closed parts of Sligo Creek Parkway and Beach Drive.

In the District, officials said all of its coronavirus testing and vaccine sites were closed Wednesday because of the storm. There was also flooding along part of Rock Creek Parkway near the Kennedy Center.

Drivers are advised to avoid flooded roadways.

Public schools in D.C., Manassas City, Manassas Park City, Arlington, Loudoun and Alexandria canceled all after-school activities. Schools in Baltimore and in Montgomery, Prince George’s and Fauquier counties closed early Wednesday because of the impending afternoon storms. Frederick County school officials announced that schools will open two hours late because of weather damage, according to a post on the county Twitter feed.

Earlier in the morning, the Cleveland Park station on Metro’s Red Line was briefly closed because of flooding.

In the midmorning, Metro riders also faced delays as trains shared a track on the Red Line between the Grosvenor and Twinbrook stops because of high water in the area.

By afternoon, Metrorail and Metrobus were operating on a normal weekday service schedule, spokesman Ian Jannetta said. The west entrance of the Cleveland Park station was closed, he said, but the east entrance remains open.

Dana Hedgpeth, Dan Morse, Ovetta Wiggins and Jason Samenow contributed to this report.