MIAMI-DADE COUNTY, Fla. – A U.S. Coast Guard serviceman from southwest Miami-Dade County shot and killed his wife and 7-year-old son early Sunday before killing himself, police said. His 8-year-old daughter was also critically wounded in the shooting.

Lt. Cmdr. Ryan Kelly, a spokesman for the U.S. Coast Guard, identified the man as Electronics Technician 1st Class John Presnar. Kelly said Presnar, 44, worked at the Coast Guard station in Miami Beach and had served in the Coast Guard since 2001.

Lt. Alvaro Zabaleta​​​​​​, a spokesman for the Miami-Dade Police Department, said Presnar and his 39-year-old wife, Gretchen Presnar, got into an argument about 1 a.m. at their home in the 11400 block of Southwest 242nd Lane. Zabaleta said when John Presnar pulled out a gun, Gretchen Presnar warned her mother to run for help.

A representative from the U.S. Coast Guard joined police outside the home.

By the time officers arrived at the home, Presnar had killed his wife and son, wounded his daughter and committed suicide, Zabaleta said.

Paramedics airlifted the daughter to Nicklaus Children's Hospital in Miami. She is listed in critical condition.

A truck parked in the driveway had a U.S. Coast Guard decal on the back window.

"The Coast Guard is deeply saddened by this tragedy and our hearts go out to the family members of those who where killed," Kelly said. "We continue to pray and offer the full support of the Coast Guard to the young child fighting for her life."

Neighbors told Local 10 News that the family was "very friendly," and they had never witnessed any problems with the family before.