Senegalese soldiers as part of a West African bloc force have crossed into Gambian territory to oust former President Yahya Jammeh.
Jammeh is refusing to cede power after being defeated in elections, causing the swearing in of Adama Barrow at the Embassy of Gambia in Dakar on Thursday..
Columns of Senegalese tanks went into the onslaught shortly after the new Gambian president Adama Barrow requested for foreign intervention by a UN-mandated Ecowas force.
The 15 member U.N. Security Council unanimously endorsed military action in The Gambia to oust Jammeh and install new President Adama Barrow.
He took his official oath of office at the Gambia High Commission on Thursday in the presence of world diplomats and requested help from members of the international community to enforce the will of the Gambian people expressed through elections in December.
The West African regional grouping Ecowas had given Jammeh an ultimatum to step down on midnight Wednesday when his term expired.
A last ditch diplomatic effort by the Mauritanian leader to persuade Jammeh to relinquish power failed.
The international community which is backing Barrow had ceased to recognize Jammeh as the legitimate leader of The Gambia after midnight Wednesday.
Throughout Thursday, Nigerian fighter jets have been flying over Gambian skies while its newest warship has been stationed off the waters overlooking State House, the seat of power where Jammeh remains holed up since last month.
Another troop contributing country to the military expedition include Ghana which is providing some 200 combat troops.