ISIS Claims Responsibility for Tunisia Terror Attack

ISIS has claimed responsibility for yesterday's lethal terrorist attack at a museum in the capital of Tunisia, calling it a "blessed invasion of one of the dens of infidels."

"Wait for the glad tidings of what will harm you, impure ones, for what you have seen today is the first drop of the rain," the group warned in a statement Thursday.

Chaos ensued at Tunisia's Bardo Museum, Wednesday, as gunmen armed with assault rifles opened fire on tourists as they got off a bus. At least 23 people died.

Among those killed were travelers from Japan, Italy, Poland, Germany, and Spain. Two of the gunmen, a police officer, a cleaner, and a security officer are also dead.

"Several shots were fired. We found another couple with their children," one witness recounted. "We didn't know what to do so we hid."

Tunisian security forces are searching for three remaining suspects.

Some believe the attack is linked to the death of Ahmed al-Rouissi, Tunisia's most wanted terrorist and a senior leader in ISIS. He was reported to have been killed Saturday in combat.

Others are concerned that ISIS has set its sights on destroying cultural heritage. Just last month, the group destroyed priceless antiquities at a museum in Mosul, Iraq.

"They have to think now, is ISIS going after cultural heritage? Are they going after museums? Could our museum be next?" Peter Herdrich, vice chairman of The Antiquities Coalition, said.

First lady Michelle Obama, traveling in Japan, expressed her condolences.

"On behalf of myself and my husband I want to join in with the others to express our condolences over the horrific event yesterday in Tunisia," she said.

Meanwhile, Tunisia's president condemned the attacks, calling them cowardly and saying that his country is in a war with terror.

"The fight against them will continue until they are exterminated," newly elected President Beji Caid Essebsi vowed in a televised address to the nation.

Tunisia's parliament met late Wednesday night, with one speaker calling for a special fund to combat terrorism, as well as for the rapid passage of an anti-terror law that parliament had been debating when the attack took place.

Experts say attacks like the one that took place Wednesday on so-called "soft targets" could become more common as extremists come under increasing pressure from counter-terrorism efforts.