Two Egyptian policemen have been killed after a bomb exploded inside a train carriage north of Cairo, police officials say.

The policemen had been inspecting the rudimentary bomb after the train, in the Menufiya province north of Cairo, stopped at a station when the explosive went off, the officials said on Wednesday.

The bomb exploded as police evacuated passengers from the carriage, also wounding eight people, state television reported.

Dozens of policemen and soldiers have been killed in attacks since the army overthrew Islamist president Mohamed Morsi last year and launched a bloody crackdown on his supporters.

Most of the deadliest attacks have taken place in the Sinai peninsula, where armed men based there killed at least 30 soldiers in one attack last month.

Source: Agencies