LINKEDINCOMMENTMORE

PETALUMA, Calif.-- Three Immigration and Customs Enforcement agents were shot and injured Thursday while serving "high-risk" warrants in the San Francisco Bay area, authorities said.

The agents suffered non-life threatening injuries during an early-morning raid in Petaluma in connection with a 2010 gang-related triple homicide, Lt. Alan Normandy of the South San Francisco police said. Multiple arrests have been made but the exact number was not immediately available, Normandy said.

The injured agents were taken to the hospital. At least one officer was airlifted from the scene as witnesses heard gunshots and loud sounds around 4 a.m. Caroline Uland, who lives nearby, told the Press Democrat of Santa Rosa (http://bit.ly/IISSzG ), that she was awakened by an explosive sound. "It was kind of frightening," she said. Bob Everhart, the manager of a nearby Best Western Hotel, told the newspaper that he heard multiple gunshots, some yelling and then a second round of gunfire.

When he went out to investigate, he was ordered to go back in. "The neighborhood was on lockdown at that point," Everhart said. A police officer told Everhart around 6 a.m. that guests could eventually leave their rooms to get breakfast. Joseph Sullivan, who lives in the area, said that an unidentified man, a woman and two children under the age of 12 lived at the house where the raid occurred.

Several other neighbors also said cars came to and from the house frequently, sometimes double-parking in the street. "To be honest, I thought they were selling weed out of the house, but obviously something more crazy was going on," Sullivan said. Dozens of officers - some in SWAT gear - swarmed the area early Thursday centered on the probe of a December 2010 drive-by fatal shootings in South San Francisco.

Gonzalo Avalos, 19, Omar Cortez, 18 and Hector Flores, 20 - who police said were alleged gang members - were gunned down while walking with a group after four men riding in a brown Chevrolet Impala with tinted windows drove up and opened fire. Three others were also wounded in the 2010 shootings. More details about Thursday's raid are expected to be released during an afternoon news conference in South San Francisco, authorities said.