EL-ARISH, Egypt (AP) — Egyptian and American officials say the deputy commander of the U.S. Central Command is paying a visit to American troops stationed in Egypt's troubled Sinai Peninsula, which has been plagued by lawlessness and hit by a string of militant attacks.

U.S. officials described Monday's visit by Vice Adm. Robert Harward as routine.

U.S. troops make up the single largest contingent of the 1,650-strong Multinational Force and Observers mission in Sinai.

The 12-nation MFO is part of the peace treaty signed by Egypt and Israel in 1979.

The officials spoke on condition of anonymity because they were not authorized to brief the media.

Egyptian authorities fired the security chief in northern Sinai on Sunday after troops came under numerous attacks by militants, who have also staged cross-border strikes into Israel.