Story highlights Spokesman: Nigerian troops are "dominating," their morale is high

Boko Haram viciously took Baga weeks ago, killing hundreds

Nigeria's military is waging an offensive aimed at the Islamist extremist group

(CNN) Nigerian troops retook the strategic northeastern town of Baga -- where hundreds were viciously killed in a Boko Haram attack last month -- on Saturday, the West African nation's top military spokesman said.

In a statement, Maj. Gen. Chris Olukolade said that "a large number of terrorists ... drowned" in Lake Chad and others were killed in the fighting to take the fishing town.

Lake Chad touches four countries -- Nigeria, Chad, Niger and Cameroon -- all of which have been targeted in recent weeks by Boko Haram, the Islamist extremist group blamed for ongoing horrific attacks, abductions and other abuses.

According to Olukolade, Nigerian troops entered Baga early Saturday morning and, hours later, moved into a "comprehensive ... search phase (to) mop up arms and ammunition and also apprehend any terrorist who might be hiding in the vicinity."

The operation in Baga was one of about a dozen being carried out in the region, all part of a Nigerian offensive aimed at ultimately crushing the terrorist group.