The U.S. is sending military aircraft and more forces to assist in the hunt for fugitive African warlord Joseph Kony, more than doubling the number of American troops and airmen on the ground to 250.

The beefed-up U.S. assistance could be “the decisive game changer” in the hunt for Kony, whose Lord’s Resistance Army appears weaker than ever before amid growing defections and the loss of senior commanders, an expert said Monday.

“The timing is right,” said Kasper Agger, an Africa researcher with the Enough Project, which works to end crimes against humanity. He said the deployment of the vertical-takeoff Ospreys “could be the decisive game changer in the mission to end the LRA.”

Pentagon press secretary Rear Adm. John Kirby said Monday that the U.S. has sent four CV-22 Osprey aircraft, two C-130 transport planes and one KC-135 refueling aircraft, along with about 150 Air Force special operations members and airmen to assist African forces. The U.S. troops and aircraft were sent from Djibouti and have arrived.

Obama sent about 100 U.S. troops in 2011 to help African Union forces find Kony, but so far the warlord has eluded them in the vast jungles of central Africa. The additional support will enable the African Union troops “to conduct targeted operations to apprehend remaining LRA combatants,” National Security Council spokeswoman Caitlin Hayden said early Monday.

“Our African partners have consistently identified airlift as one of their greatest limiting factors as they search for and pursue the remaining LRA leaders across a wide swath of one of the world’s poorest, least governed and most remote regions,” Hayden said.

The aircraft will be based in Uganda and will be used in Central African Republic, Congo and South Sudan, she said. The U.S. advisers are assisting about 2,500 African Union troops to chase LRA fighters in a jungle about the size of France.

The LRA is accused by the United Nations and human rights groups of killing and mutilating innocent civilians and kidnapping thousands of children, forcing them to become soldiers and sex slaves.

The CV-22 Osprey is a versatile aircraft that can fly like a plane and a helicopter. Its ability to take off and land vertically should make it effective in the heavy jungle areas where the troops are operating.

“These aircraft are very helpful. They enhance our capacity, particularly in the search operations, reconnaissance, airlifts,” said Ugandan military spokesman Lt. Col. Paddy Ankunda.

The LRA originated in Uganda in the 1980s as a tribal uprising against the government. In 2005, Kony became the first suspect to be indicted by the International Criminal Court on charges of war crimes and crimes against humanity.

After it was ousted from Ugandan territory in 2005, the group scattered into parts of Congo and Central African Republic. There are between 200 to 500 LRA fighters still active in the jungle, according to estimates from the Ugandan military and the Enough Project.

Kony himself is believed to be hiding in the border region between Central African Republic and Sudan’s South Darfur region.