Jesus Camacho Nunez and Miguel Angel Galvan-Morfin, both 21 of Santa Rosa, were allegedly attempting to flee the United States and were apprehended Monday in San Ysidro, a community in San Diego, Sgt. Rainer Navarro said.
The federal agents also arrested a 17-year-old suspect Wednesday in the San Ysidro area, Navarro said.
A fourth suspect, Lorenzo Medina, 27, was arrested in Santa Rosa on July 22.
The stabbing happened in the 900 block of Washington Avenue at about 8 p.m. on July 21.
Police say the suspects chased the 17-year-old boy, who is believed to be a member of a rival gang, several blocks and stabbed him at least 15 times.
The teen's injuries were not life-threatening, police said.
Nunez and Galvan-Morfin were arrested by U.S. Customs and Border Protection agents, then returned to Sonoma County and booked into jail for attempted murder and gang-related enhancements, Navarro said.
The teenage suspect is being held in a San Diego juvenile detention facility and will be extradited to Sonoma County to face the same charges, Navarro said.