WASHINGTON (AP) — The Pentagon says airstrikes in Syria and Iraq are the beginning of a “credible and sustainable, persistent” campaign to degrade and ultimately destroy the Islamic State militant group.

Lt. Gen. William Mayville, director of operations for the Joint Chiefs of Staff, tells reporters at the Pentagon that future strikes can be expected.

The U.S. and five Arab nations joined in airstrikes Monday and early Tuesday against the Islamic State group’s headquarters in eastern Syria, using land- and sea-based U.S. aircraft as well as Tomahawk cruise missiles launched from two Navy ships in the region. American warplanes also carried out eight airstrikes to disrupt the shadowy Khorosan Group, a network of seasoned al-Qaida veterans suspected of plotting attacks against U.S. and Western interests.

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