DALLAS — A former Texas special education teacher, described by a colleague as a “gentle giant,” fatally shot four people including his estranged wife and current girlfriend, in a spasm of apparent domestic violence, police said on Thursday.

Four other people were wounded, three of them critically, in the attacks late Wednesday night in a home in Dallas and another house in DeSoto, a suburb about 15 miles south of Dallas, said Corporal Melissa Franks of the DeSoto Police Department.

Erbie Bowser, 44, was charged late on Thursday with murder in the deaths of his estranged wife Zina Bowser, 47, and her daughter Neima Williams, 28, Franks said.

Also dead were Bowser’s girlfriend, Toya Smith, 43, and her daughter Tasmia Allen, 17, said Dallas Police Major Jeff Cotner. Charges against Bowser in connection with those shootings were being prepared, he said.

The four wounded included three boys, ages 11, 13, and 14, all in critical condition, and a 17-year-old girl whose condition was not given, police said.

None of the four wounded were related to Bowser, police said.

Bowser was a well-liked special education teacher, in Mesquite, Texas, who resigned in 2010, said Laura Jobe, a spokeswoman for the Mesquite Independent School District.

“He had a good history here,” she said. “He’s been described as a gentle giant.” He also coached football in Mesquite, she said.

Bowser had also been a member of a dance team for the Dallas Mavericks professional basketball team but left the squad in 2009, the team said.

Police said the first emergency call came late on Wednesday evening from a woman who became concerned after speaking by phone with someone at the Dallas home. She drove to the house but no one answered.

Another emergency call was received from the DeSoto residence.

“We do believe this is a domestic-related incident,” a police official said.

All of those killed were believed to have died from gunshot wounds, although Franks said an explosive device was used as well.

It was too early to say what type of device was used and samples were sent for laboratory testing, said Russ Morrison with the Bureau of Alcohol, Tobacco, Firearms and Explosives.

Bowser had military training, serving in the U.S. Army from 1991 to 2000, a U.S. Army spokesman said. He reached the rank of sergeant and received several medals, including one for good conduct, and an “Expert Infantryman” badge, he said.