"It’s a tragic event here in San Diego, and probably one of the bigger vessel accidents and one of the bigger calls we’ve seen here," James Gartland, lifeguard chief for the City of San Diego, said at a press conference
boat crash
Credit: San Diego Fire Department

At least four people were killed and dozens more injured after a boat that authorities said was likely being used to smuggle migrants into the United States crashed against a reef and broke apart off the coast of San Diego.

The 40-foot cabin cruiser, which authorities said was "way overcrowded" with about 30 people, was destroyed on the shore line near the Point Loma Tide Pools in the Cabrillo National Monument around 10 a.m. on Sunday, the U.S. Coast Guard said in a news release.

By the time authorities arrived on scene, the boat had "been basically broken apart," Rick Romero, lifeguard lieutenant with the San Diego Fire-Rescue Department, said at a press conference on Sunday afternoon.

"The first report from the commercial assistance vessel was three or four people waving for help. That turned into [many] more people as we started getting on scene," Romero said. "There were people in the water drowning, getting sucked out with the rip current there."

Lifeguards were able to make seven water rescues and one cliff rescue, James Gartland, lifeguard chief for the City of San Diego, said at the press conference. He said three people were given CPR, and one person suffered "major trauma" as the nearly two dozen victims were sent to multiple hospitals throughout the county.

According to the Coast Guard, four people were declared dead by local emergency services personnel as of Sunday night, and one person remained in critical condition.

In addition to the multiple agencies, two personal watercrafts and three boats used in the rescue, Romero said a Navy staff member who was in the area with his family jumped in to help, too, amid conditions that were "pretty rough," with 60-degree water and five to six feet of surf.

"The boat was on the reef, bouncing back and forth, and then just slowly disintegrated into a bunch of pieces," he said. "So there's no boat there, it's all debris."

RELATED VIDEO: At Least 13 People Dead in Calif. Crash Involving Tractor-Trailer and SUV Carrying 25 People

Jeff Stephenson, Border Patrol supervisory agent in the San Diego sector, said at the press conference that authorities believe the "severely overcrowded" boat was being used to smuggle people illegally into the United States.

He said the nationality of those involved has not been confirmed, but that the captain of the boat is in custody.

"The smugglers, they don't care about the people they're exploiting, all they care about is profit," he said. "To them, these people are just commodities, and you can see that in the way that they treat them. Inadequate safety equipment, really poorly equipped vesesls. They give them flotation devices and life jackets, but they're old, they're tattered, it's not like normal equipment you see, and they pack them on to these vessels."

Stephenson said that boats containing migrants typically try to "blend in" with other commercial traffic to avoid being caught. The boat's origin remains unclear, though Stephenson said boats like the one that capsized typically come from the Rosarito area in Mexico, or other beaches along the Baja Coast.

It remains unclear whether there were any children on the boat, and also whether the victims were male or female.

"This is a tragedy. It's a tragic event here in San Diego, and probably one of the bigger vessel accidents and one of the bigger calls we've seen here," Gartland said. "Certainly in my 26 years and certainly in Lt. Romero's 28 years, this is probably the worst tragedy."