The U.S. Marine Corps has given the F-35B Lightning II aircraft from Lockheed Martin Initial Operational Capability.

With the declaration last week, Marine Fighter Attack Squadron 121, or VMFA-121, in Yuma, Ariz., can deploy its 10 aircraft on operations wherever they may be needed.

"I am pleased to announce that VMFA-121 has achieved Initial Operational Capability in the F-35B, as defined by requirements outlined in the June 2014 Joint Report to Congressional Defense Committees," said Gen. Joseph Dunford, Commandant of the Marine Corps. "VMFA-121 has 10 aircraft in the Block 2B configuration with the requisite performance envelope and weapons clearances, to include the training, sustainment capabilities, and infrastructure to deploy to an austere site or a ship.

"It is capable of conducting close air support, offensive and defensive Counter air, air interdiction, assault support escort and armed reconnaissance as part of a Marine Air Ground Task Force, or in support of the Joint Force."

IOC was granted following a five-day readiness inspection and seven weeks of testing from an aircraft carrier at sea, during which time shortfalls in capability were reportedly uncovered.

The B variant of the F-35 is to replace the Marine's AV-8B Harrier, the F/A-18 Hornet, and the EA-6B Prowler.

The U.S. Marine Attack Squadron 211 -- an AV-8B squadron -- is expected to transition to the F-35B in fiscal year 2016.