A passenger train struck the back of another train outside London on Saturday, sending rail cars careening into the yards of nearby homes and killing at least five people, police said. At least 80 people were hurt.

Earlier death tolls in the capital's second major rail accident in less than three months ran as high as 12 but could not be confirmed.Scotland Yard put the confirmed death toll at five dead and 80 injured. Earlier it had said six died. It did not explain the change.

St. Helier Hospital reported two deaths there, and Mayday Hospital's emergency chief, Kambiz Hashemi, said three people were dead at that hospital.

Reports of deaths reached 12 earlier in the day when Hashemi reported four dead at Mayday and six more dead at the scene of the crash - a claim that could not later be confirmed. There also was apparent confusion over the number of times the two deaths at St. Helier had been counted.

Hashemi said his hospital admitted 52 casualties, 20 of them in serious or critical condition. Twenty-four were discharged and three transferred to hospitals specializing in head and spinal injuries.

Firefighters had to cut dozens of passengers from the wreckage of the trains, and authorities said some were trapped for hours after the 1:39 p.m. collision near the Purley station in Surrey.

Both trains originated in southeast England cities and were traveling north to London.

A British Rail spokesman said it appeared a train that originated in Horsham, West Sussex, was crossing from the local line to a main track when it ran into the back of a train that originated in Littlehampton.

Littlehampton is about 50 miles south of London and Horsham is about 30 miles south of the city.

The spokesman, speaking on condition of anonymity, said it was not known why both trains were on the northbound track at the same time.

The trains collided a few hundred yards outside the station on London's southern outskirts, sending several cars hurtling down an embankment into the yards of homes, witnesses said. It was not known if anyone was hurt in the houses.

Several rail cars came to a precarious rest on the steep slope, and residents were advised to leave their homes until the wreckage could be cleared.