Cairo, June 17 (IANS): An Egyptian policeman was killed on Wednesday and three others were wounded in a bomb explosion in the city of al-Arish in the Sinai Peninsula, the country's interior ministry said.

The device was placed underneath an armoured vehicle and was detonated when police were patrolling a main street in central al-Arish, Efe news agency reported citing a statement issued by the ministry.

Those wounded were taken to a hospital and were in stable condition. the security forces conducted raids to catch the "terrorists".

Security forces have been on high alert since the attack, according to the official MENA news agency

Meanwhile, Egyptian armed forces spokesman Mohamed Samir said they killed at least seven suspected jihadis on Wednesday in the area of Sheikh Zuweid in North Sinai.

Samir added on his official Facebook page earlier in June that the forces reportedly killed 141 suspected jihadis in May during various military operations in North Sinai.

A state of emergency and a curfew have since been imposed in several areas in North Sinai.