A D.C. police officer shot and killed a Southeast Washington man yesterday after he aimed a gun at the officer, who was investigating a report of an armed man outside a house, D.C. police said.

In a separate incident earlier in the day, a D.C. police officer shot and wounded a Northeast Washington man who pointed a gun at him.

The earlier incident was the seventh fatal shooting in the last five weeks by law enforcement officers who believed their lives or the lives of bystanders were threatened.

Seventh District police officer William R. Haupt, 45, fatally shot Reginald White, 32, of 3058 Stanton Rd. SE, after White pointed a semiautomatic handgun at him, police said. Haupt and another officer from the 7th District were responding to a phone call about a man brandishing a gun at 1409 Alabama Ave. SE.

Police said the two officers found White on the front porch of the brick row house on Alabama. When they told him to drop the gun, White turned and pointed it at one of the officers, police said.

"At this point, the officer, believing that serious bodily injury or death could occur, fired two shots, striking {White} in the head and the chest," according to a police statement. White was taken to the D.C. medical examiner's office, where he was pronounced dead at 12:30 p.m.

Haupt, a 16-year veteran, has been placed on routine administrative leave with pay while the shooting is investigated, police said.

In a separate incident at 3 a.m. yesterday, another 7th District officer, John M. Roeder, shot Richard Coates, 26, of 10 Girard St. NE, after Coates pointed a gun at him, police said. Coates has been charged with assault on a police officer while armed.

While they were on routine patrol, Roeder and a 7th District detective saw two men arguing at Joliet and Irvington streets SW, police said. When the officers tried to break up the altercation, one man pulled out a gun. After a struggle with the detective, whom police would not identify, the man aimed the handgun at Roeder, police said. Roeder fired at him three times, apparently striking him once, and the gunman fled. The second man apparently fled during the shooting, police said. Police searched but were unable to find either man.

Thirty minutes later, police said they received a call about a man complaining of pain at 4809 First St. SW. After investigating the report, police found the man, who they believe had earlier pointed a gun at Roeder.

Coates was taken to Greater Southeast Community Hospital, where he was admitted in stable condition. Roeder, 35, an officer for 15 years, remains on active status.

The following killings involving police officers have occurred in recent weeks: On Nov. 16, Jose Carlos Rodriguez, of no fixed address, was fatally shot by Fairfax Investigator Irene M. Boyle during a drug arrest. Police said the shooting was accidental.

On Nov. 21, Wesley Scott Gaskins, 28, of Southwest was shot to death by police marksmen after he wounded two D.C. officers during a foot chase.

Also on Nov. 21, George P. Valltos, 37, of Germantown, was shot to death outside a Gaithersburg hotel after he allegedly attacked Harold K. Allen, an off-duty Montgomery officer working as a security guard, with a flashlight.

On Dec. 4, David Anthony Bane, 17, of Wheaton was fatally wounded after turning on Michael J. Jones, an off-duty Montgomery officer, with a baseball bat. Jones had been trying to break up a brawl at a north Wheaton gas station.

On Dec. 12, Richard F. Calvird of Louisiana was shot to death while attacking Prince George's Sgt. Benny G. Gilbreath with a Bowie knife on a Capital Beltway off-ramp in Bethesda. Calvird attacked the off-duty officer after their vehicles were involved in a minor traffic accident.

On Dec. 14, D.C. police Officer James L. Gordon, 40, was fatally shot by Prince George's Cpl. Robert W. Raimond, who was investigating a burglary at Gordon's home in Largo.