WASHINGTON (CBSDC) – Former CIA deputy director Michael Morell tells CBS News he has serious doubts that the Islamic State of Iraq and Syria was behind Sunday’s attack on a Muhammad cartoon contest in Garland, Texas.

“There is no evidence that ISIS directed the attack, no evidence that they were in communication with these two individuals,” Morell said on “CBS This Morning.”

On Tuesday, ISIS claimed responsibility for the attack, in which only the gunmen were killed, though a security guard was injured.

Morell called the claim dubious and said he believes the gunmen, Elton Simpson and Nadir Soofi, were self-radicalized.

“This was not a successful attack. There was no open devotion by these individuals to ISIS,” he added.

The fact that ISIS tried to take credit for the gunfight in Texas is a sign the militants are losing their grip on power.

“I actually think this might be a sign of weakness, a reflection that they see that their momentum has slowed a bit,” said Morell.

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