Seventeen people were detained Friday after a panga was spotted off the coast of the Palos Verdes Peninsula, federal authorities said.
A bystander alerted local police after spotting the 25-foot fishing boat about 8:30 a.m. near Lunada Bay, said Virginia Kice, a spokeswoman for U.S. Immigration and Customs Enforcement. Federal authorities were called to the scene and detained the 15 men and two women who were aboard.
Kice said four of the people were taken to area hospitals for treatment -- two who were injured when the boat came ashore, one suffering from exposure and another from hypothermia. Kice said none of the injuries appeared to be life-threatening.
The remaining 13 people were taken to the San Clemente Border Patrol station to be processed and interviewed, Kice said. Investigators were still trying to determine their nationalities.
No drugs were found aboard the craft, Kice said.
Kice called Friday's discovery a reminder how "very, very dangerous" pangas can be for those aboard. The four people injured had to be airlifted to the top of a bluff to be examined, she said.
"We hope it serves as a warning to anyone considering attempting to come to the U.S. in this way that this is not the way," she said. "When you see these open, small boats -- it's mind-boggling to think people would get in one of those and go out in the open ocean."
Pangas have become popular among smugglers to ferry drugs or people up the California coast. The latest ICE statistics show 85 boats were seized along the coast between October 2013 and early March, compared with 96 incidents in the same time period a year earlier.
Most -- 59 -- occurred in San Diego County, ICE said. Five of the pangas found there were smuggling marijuana or methamphetamine; the remainder carried people.
Three boats were seized in Orange County, and two each in Los Angeles and Ventura counties, ICE said.
In 2012, Coast Guard Chief Petty Officer Terrell Horne III was killed when a panga rammed his boat off the coast of Santa Barbara. Horne, who was posthumously promoted to the rank of senior chief petty officer, was thrown from the craft and struck in the head by a propeller.
In February, the two Mexican nationals aboard that panga were convicted in Horne's death. Jose Meija-Leyva, 42, of Ensenada was found guilty of second-degree murder and six other counts, including assaulting federal officers with a deadly and dangerous weapon, the U.S. attorney's office said. Manuel Beltran-Higuera, 44, also of Ensenada, was convicted as an accessory after the fact.