CNN  — 

Three Iraqi officers were killed and 10 others wounded early Thursday when two suicide bombers blew themselves up at a police station in western Baghdad, authorities said.

The Sunni terror group ISIS claimed responsibility for the attack in a statement, saying that 20 police officers had died.

Police said two men wearing suicide vests targeted al-Entisar police station in the historically volatile Abu Ghraib district of Iraq’s capital.

Security officials told CNN that the terrorists tried to storm the police station around 5 a.m. local time (10 p.m. Wednesday ET).

The two suicide bombers and a third armed man went to launch their attack, but security forces were able to kill the armed man. However, the other two detonated their vests, causing multiple casualties.

Deadly 48 hours

This latest attack comes after one of the bloodiest days in the Iraqi capital this year when more than 90 people were killed in three separate bombings targeting Shiites for which ISIS claimed responsibility.

In Wednesday’s violence, 64 people were killed when a car bomb went off at a Baghdad market, Iraqi police said. An additional 87 people were wounded in the attack in the largely Shiite neighborhood of Sadr City.

Later Wednesday, a suicide bomber detonated in a busy square in the Shiite neighborhood of al-Kadhimiya in Baghdad, killing 17 people, and a suicide car bomber exploded at a checkpoint manned by Shiites in the Sunni neighborhood of al-Jamia, killing 12.

Political risk analyst Kirk Sowell said the jihadist group’s tactics are changing as it loses grip on territory.

“ISIS has receded somewhat militarily; they don’t have a … standing army to hold territory,” Sowell said. “But what they’re good at unfortunately is these terrorist attacks against soft targets.

“(Wednesday) was worse than most, but in the last few months there’s been this increased focus on terrorist attacks going back to pre-2014 tactics.”

ISIS changing strategy

U.S. Sen. Angus King, a member of the Senate Intelligence and Armed Services committees, agreed, telling CNN that the terror group was changing its strategy as it loses ground in Iraq and Syria.

“Now what they’re trying to do is foment a sectarian war in Iraq between Sunnis and Shia and that just further complicates the situation,” King said.

“The key question now is can the government in Baghdad gain control, gain some consensus and actually start to govern that country? Or is it going to splinter on sectarian grounds, in which case it’s going to be very difficult, very difficult to control ISIS.”

He said the “big gap” in the U.S. strategy against the group was the lack of an army on the ground in Syria.

“That’s not where Americans should be, that would be a gift to ISIS,” he said. “But finding the people to take the fight to ISIS in those towns, that’s a problem.”

Group losing ground

ISIS declared its so-called Islamic caliphate over stretches of Iraq and Syria in June 2014 but has since come under attack on multiple fronts – by Iraqi, Syrian and Kurdish forces and various international actors, and lost significant territory.

In Iraq, two major cities, Tikrit and Ramadi, have been reclaimed from the group as well as a number of significant towns.

FBI Director James Comey said Tuesday that ISIS’ online appeal seems to be dwindling as well – at least to potential U.S. supporters.

Using another name for the group, Comey said that “the ISIL brand has lost significant power” and cited a decrease in Americans traveling or attempting to travel to fight with the group – from between six to eight a month in the past two years to about one a month now.

Opinion: ISIS is losing the war