A 32-year-old man bought crack cocaine before fatally shooting his girlfriend and then himself in a murder-suicide in the Dorchester Manor subdivision, authorities reported Tuesday.

Dorchester County Coroner Chris Nisbet identified the couple as Du Xuan Dao, a 32-year-old Vietnamese man, and Mong Thuy Thi Doan, a 27-year-old Vietnamese woman.

Sheriff's deputies were called to the couple's home on Dorchester Manor Boulevard around 6 p.m. Monday for a welfare check, Chief Deputy Sam Richardson said.

Dao and Doan were found dead inside the single-story brick house with gunshot wounds to their heads, Nisbet said. Authorities believe they died Christmas Day.

Selena Walker, a neighbor, looked out of her window and saw several deputies' cruisers illuminating the night on Monday.

"I assumed it was just someone arguing," Walker said. She said she was shocked to hear that the dispute was much more serious than just that.

"As long as I've been living here, that has never happened. This side of the neighborhood is usually pretty quiet," Walker said.

A silver BMW remained parked in front of the home Wednesday morning. Neighbors said the vehicle belonged to the couple.

A loved one told authorities that the couple had two children who had traveled to Vietnam for the holidays, Nisbet said.

Dao's drug use was a point of contention for the young couple, authorities said.

Sheriff's deputies previously responded to the home around 2:30 a.m. Dec. 14 after a neighbor reported a disturbance.

According to an incident report, Doan appeared to be in distress when she ran up to the deputies who entered her home. She directed them toward Dao, who was busy flushing crack cocaine down a toilet, the report said.

Authorities searched the home and found two glass pipes in the bottom of the commode. Doan told deputies that Dao used the pipes to smoke crack.

She acknowledged arguing with Dao that night, but Doan denied that he hit her, the report said.

Dao was charged with possession of drug paraphernalia and held at the Dorchester County jail in the incident. He was released Dec. 21 after posting $500 bail, then shot his girlfriend to death four days later, authorities said.

According to Nisbet, Doan spoke with her mother almost daily, but family members hadn't heard from her daughter since Christmas. A friend reported that Dao purchased drugs the day the shooting is said to have occurred, Nisbet said.

Ottie Mae Plum, a blind woman, lives next door to the couple's home.

Plum said her neighbors mostly kept to themselves. But she recalled hearing a man, who she believed to be Dao, pacing back and forth in the couple's yard apparently singing and praying to himself in the days before the shooting.

"I couldn't understand what he was saying - it was in their language. But it scared me so much I went back inside my house," Plum said.

A loud pop caused Plum to jump out of her chair days later on Christmas. She couldn't see the source of the noise but assumed at the time that someone was playing with firecrackers. After hearing of her neighbor's death, Plum questioned whether what she heard was actually gunfire.

Another neighbor, who would not give his name, said he called authorities after hearing a woman screaming and someone kicking at the home's walls in the days leading up to Christmas. He said deputies responded, but the woman did not appear injured.

The Sheriff's Office could not immediately confirm that account Wednesday, and an incident report for the murder-suicide was not available. Sheriff's deputies did not provide further details on the incident.

Reach Christina Elmore at 93 7-5908 or at Twitter.com/celmorePC.