CAIRO, Feb 12 (Aswat Masriya) - Police and army forces arrested 13 people, including three infiltrators from the Gaza Strip, in North Sinai on Wednesday, an armed forces spokesman said.

The arrests were part of a crackdown on several villages in Arish and Rafah.

Among the arrestees are five pro-Muslim Brotherhood extremists, spokesman Ahmed Ali said in a statement.

The army demolished eight tunnel entrances that were used to smuggle individuals and goods between Gaza and Egypt, the statement said.

Ali also said that the army set alight one motorcycle and three cars with no number plates that extremists were using in their assaults on the police and the army.

Army and police forces have launched crackdowns on different parts of Sinai after extremists intensified their attacks on security forces following the ouster of former President Mohamed Mursi.