A man fatally shot three people Friday and was found dead with a suicide note in the second deadly shooting in three days, prompting South Korean police to announce plans to tighten regulations on gun ownership.

Gun possession is tightly controlled in South Korea, with only one murder with a firearm reported last year. But hunting weapons, like a shotgun in Friday's killing spree, are allowed.

The victims included a policeman, who was one of the first officers to respond, according to police in Hwaseong city, near Seoul. The 75-year-old suspect is believed to be the brother of an 86-year-old victim, whose wife was also dead, police said.

The suspect was found with gunshot wounds in his chest and near his right armpit in what the police believed to be a suicide.

The daughter-in-law of the dead couple managed to escape by jumping from a second-floor window before alerting the police, and is currently being treated for a minor back injury. All four were found in the first-floor living room and a shotgun was near the suspect, Hwaseong police chief Lee Seok-kwon said in a televised briefing.

A suicide note found in his car and testimonies of other family members suggested a turbulent relationship with the dead couple, Lee said. It was believed that the slain officer, who wasn't wearing a bullet-proof vest and armed only with a stun gun, tried to talk the suspect into surrendering before being fatally shot in the chest.

The suspect had retrieved the shotgun from a nearby police station about 20 minutes before the shooting.

South Koreans can obtain licenses for shotguns and air rifles for the purpose of hunting, but they are required to keep the weapons at police stations and use them only during legal hunting periods. It wasn't immediately clear whether the suspect owned the gun or had a proper license for it.

The deaths follow a shooting on Wednesday, when a man killed three people in central Sejong city before apparently turning the gun on himself.

According to the National Police Agency, South Koreans legally owned about 160,000 guns as of January, a figure that included hunting weapons and self-defense tools such as gas-emitting guns.

The police agency said Friday it plans to tighten regulations on gun ownership, including strengthening the screening of those seeking to license a weapon and shortening renewal periods.

While murders involving firearms are rare, there has been a spate of shooting deaths among soldiers in recent years. Last year, a conscript killed five colleagues, telling investigators he had been bullied by the victims. Earlier shooting rampages at other front-line units in 2005 and 2011 left 12 soldiers dead.