Nigeria’s military launched a co-ordinated air, naval and ground assault to free 19 hostages held in militant camps in the oil-rich southern delta, apparently routing the gunmen without causing any casualties.

Nigeria’s acting president dissolved the Cabinet today in his first major act since taking office more than a month ago.

Negotiators worked to free four foreigners held hostage in Nigeria’s southern oil region as militants claiming to hold the captives said they would target oil installations if their demands were not met within days.