It began as a typical, carefree holiday weekend at the popular Colombian tourist destination, a scenic reservoir surrounded by mountains and greenery that draws throngs every weekend for fishing, water sports and all-inclusive boat cruises.

But at about 2 p.m. Sunday on the El Peñol-Guatapé reservoir near Medellin, Colombia, one of these boat cruises took a deadly turn.

About 160 people were aboard the four-level, teal-and-yellow boat adorned with pictures of sailboats on its sides, its name “El Almirante,” The Admiral, painted in cursive. Within minutes, it capsized.

“Five minutes after leaving everything was normal” a survivor told Colombian newspaper El Tiempo. Then passengers heard a loud noise and saw the lights go out.

Dramatic video captured scores of panicked passengers fighting their way to the upper decks, crowding on one side of the boat as it rocked back and forth. Survivors told local press that none of the passengers wore life jackets.

“There were many screams, and water began to fill us up quickly,” the survivor said. “I grabbed two kids and got ready to swim.”

As of early Monday, six people are reported dead as a result of the boat’s capsizing, Colombian authorities said. The number is likely to change.

About 133 people had been rescued and an additional 16 people were still missing, Colombia’s national disaster risk management agency said late Sunday night. Colombian president Juan Manuel Santos, who arrived in Guatapé Sunday night to meet with response teams, had said earlier Sunday that 31 were missing.

The number of fatalities also fluctuated throughout the afternoon and evening, with Colombian authorities previously saying that nine people were dead and then six. Officials said it is not yet clear why the boat sank.

Margarita Moncada, the head of the disaster response agency in Antioquia state, told reporters that 99 people were rescued immediately, followed by two groups of 40.

Search teams and specialist divers continued to look for missing passengers late Sunday but suspended efforts overnight due to weather.

Video footage showed motorboats and Jet Skis swooping in to help rescue passengers as the boat capsized. Masses of people gathered at the shore of the man-made lake, awaiting survivors rescued from the water.

Survivors said the boat “split,” and the captain instructed passengers to move to one side, El Tiempo reported.

“We saw things that were flying off the boat,” a survivor told the BBC. “I think in just 20 seconds the boat had sunk, leaving only the upper deck visible, so everything went very fast.”

“We were taking photos, seeing that it was very beautiful the day when from one moment to another we felt the loud noise,” José Gilberto Villegas, who had boarded the vessel with 23 people he knew, told the news agency EFE. “Everyone shouted and pleaded ‘help, help.’ ”

As water flowed onto the boat, passengers were sucked under it, the Associated Press reported.

“Those on the first and second floors sank immediately,” survivor Lorena Salazar told local media, the AP reported. “All we could do was scream and call for help … it was completely chaotic.”

A survivor named Éder Tobón told Colombian news station BLU Radio the water flooded the boat through the windows.

“I found a life vest, put it on a boy and placed him on a boat,” he said, adding that he saw only a few floating devices in the area of the boat storing life jackets.

“When the boat was sinking, I went inside the first two levels and there was a woman with a broken arm,” Tobón added.

Witnesses said it was not the first accident involving “The Admiral.”

Marilyn Usme, a merchant who witnessed Sunday’s shipwreck, told BLU Radio that the same boat sank at the dock three months ago, but “the owner ordered it to be fixed.”

No passengers were aboard the last time the boat sank, she said.

Sally Palomino, a reporter for Spanish newspaper El País, tweeted that she and her mother were on the same boat one month ago. When they asked for life vests, they were told they were overreacting.

One woman, a native of Santander, Colombia, told El Tiempo she and her husband managed to find floating devices so they could safely escape with four others. She was still in shock while speaking to reporters, and did not yet know where her father was.

Brig. Gen. Óscar Gómez, local police commander, said response teams would work as long as necessary to rescue people.

“We have already begun the investigation into what happened, but we are focusing on the rescue,” he said.

A woman on Facebook identifying herself as a native of nearby Medellin said the water in the reservoir is very cold, and “at night, the temperatures drop.”

After sundown Sunday night, the AP reported, the usually bustling tourist town was quiet.

“Guatapé is mourning,” posts on social media read in Spanish.

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