By Andrea Lorenz
HOUSTON (Reuters) - A gang fight that left one teenager stabbed to death and three others injured at a suburban Texas high school started with a shoulder bump in the cafeteria before school on Wednesday, authorities said on Thursday.
High school student Luis Alonzo Alfaro, 17, told police that he approached classmate Joshua Devon Broussard and some friends in the cafeteria of Spring High School, north of Houston, said Jeff McShan, spokesman for the Harris County District Attorney.
Alfaro told police that he purposely bumped into Broussard, also 17, whose friend then lunged toward him, McShan said.
That's when Alfaro pulled out a pocket knife, "covered his face with his left forearm and swung (the knife) in a back and forth motion," McShan said, based on what Alfaro told investigators.
Broussard died at the school and three others were treated and released at hospitals on Wednesday. Alfaro was charged with murder with bail set at $150,000 on Thursday morning, according to court records.
Wednesday's stabbing was the third such violent incident at a Houston area school this year. Fourteen people were stabbed, but none killed, at a community college campus in April, and three people were wounded in a shooting at another community college campus in January.
Police will not disclose the gangs they believe were involved in Wednesday's incident. But investigators believe that all those involved are gang members, based on interviews with participants and witnesses, said Christina Garza, spokeswoman of the Harris County Sheriff's Office.
The Spring Independent School District, located about 25 miles north of Houston, has about 36,000 students. It reported 15 gang-related violence incidents to the Texas Education Agency during the 2011-2012 school year, according to data kept by the state.
The pastor of one of the injured boys and Broussard's father disputed allegations of gang involvement during interviews on Wednesday.
(Editing by Brendan O'Brien, Cynthia Johnston and Cynthia Osterman)