A truck coming down a hill plowed into rescue workers and gawkers at the site of an earlier collision _ a double accident that killed at least 28 people and injured 90, police said.
The first crash occurred when one truck tried to pass another on a curve and smashed into an oncoming bus with about 20 people aboard in the southern state of Santa Catarina, highway police spokesman Adrian Fiamoncini said on Wednesday. Six people on the bus and the truck driver were killed.
"It was a serious accident but everything was under control," Fiamoncini said. But about 90 minutes later, "all of a sudden for no reason another truck arrived and ran everybody over, firefighters, police, people who stopped at the scene," Fiamoncini said.
He said it was still unclear why the other truck failed to stop but said it might have lost its brakes.
The second accident killed 21 people, including three firefighters and a policeman, he said. The driver of the second truck was hospitalised under police custody.
Fiamoncini said many of the injured remained in serious condition and that rescue workers were still looking for other victims.