SAO PAULO, Brazil (AP) – Rescue crews aided by dogs searched into the night Saturday for occupants of a minibus and other possible victims feared buried in a huge crater after the earth gave way at a construction site for a new subway station.

Witnesses told police that a minibus with a driver, fare collector and two passengers fell into the crater when a 130-foot-wide circular hole lined with concrete walls at the site collapsed Friday, said Etrusco Juarez, a spokesman for Sao Paulo’s state public security department. Two pedestrians and a truck driver who was working at the construction site were also missing and may be buried under the rubble, the government’s Agencia Brasil news agency said.

The search effort continued after darkness set in Saturday, and authorities said it was possible there were still survivors more than 24 hours after the accident.

But rescuers had not found any sign of the minibus or possible victims by late Saturday night.

“We’re making every possible effort in the search for the people who disappeared,” Sao Paulo state Gov. Jose Serra told reporters at the site.

The hole at the construction site collapsed without warning Friday, creating a crater about 260 feet wide and 125 feet deep. It swallowed cars and dump trucks along one of the busiest traffic corridors in South America’s largest city.

Two cars were removed from the rubble Saturday and a 55-ton crane teetering at the edge of the hole was stabilized. More than 100 people living nearby were evacuated, however, for fear the crane may still topple over, Sao Paulo’s Civil Defense Department said in a statement.

The cause of the collapse was under investigation, but the consortium of Brazilian companies building the subway station said in a statement that heavy tropical rains may have contributed by softening the ground under the site.

“All efforts are focusing now on the rescue of possible victims,” said Consorcio Via Amarela, a group that includes Constructora Norberto Odebrecht SA, Brazil’s largest construction company. The consortium denied that the accident was caused by negligence.