PHNOM PENH, CAMBODIA - A 50-year-old British man has been arrested for a second time in Cambodia on suspicion of sexually abusing underage girls, one as young as 11, police said Monday.

Michael Julian Leach, from London, was arrested at a guesthouse near Phnom Penh on Sunday, said Keo Thea, chief of the capital's anti-human-trafficking and juvenile protection unit.

"Police had followed him from Phnom Penh because we knew in advance that he would go to find children in Kandal province," he told AFP.

Leach, in Cambodia as a tourist, was being held for allegedly soliciting sex from two girls aged 11 and 13, Keo Thea said, adding that three Cambodian people were also arrested for procuring the girls.

Leach was first arrested in Cambodia 2005 - when he was working as a doctor at a children's organisation - for allegedly having sex with three underage girls, police said.

He was freed after the court dropped charges against him, citing a lack of evidence.

Dozens of foreigners have been jailed for child sex crimes or deported to face trial in their home countries since Cambodia launched an anti-paedophilia push in 2003 in a bid to shake off its reputation as a haven for sex predators.