LOS ANGELES - STATE regulators were investigating on Wednesday how two two-year-old infants managed to escape from a day-care center and make their way to a train track, where they were discovered by a passerby.

The two boys had been playing outdoors at a YMCA day care centre in Anaheim, near Los Angeles, last Thursday and were discovered missing when supervisors at the day-care conducted a head count, the centre said.

The wandering pair were then spotted playing alongside train tracks near the daycare centre by a passerby, who moved the two boys away from the area and called police, Anaheim Police Sergeant Rick Martinez told the Los Angeles Times.

California's Department of Social Services said it would investigate the incident, and the day-care said it also would carry out an inquiry.

'We are conducting a full investigation into the matter, reviewing all safety procedures and doing everything else within our power to ensure that something like this could never happen again,' the centre said in a statement. -- AFP