The U.S. military said on Saturday a U.S.-led coalition strike had hit a Deash-held area of Iraq's Mosul where residents and officials say as many as 200 civilians may have been killed as result of an air raid.The American confirmation followed a decision by Iraqi government forces to pause their drive to recapture west Mosul on Saturday because of the high rate of civilian casualties, a security forces spokesman said, a move apparently motivated by the incident.The statement issued by the U.S.-led coalition said the airstrike had been requested by Iraqi security forces to target Daesh fighters and equipment "at the location corresponding to allegations of civilian casualties." U.S.-backed government troops were fighting Daesh forces in that area of western Mosul, the statement said. The coalition said it takes all allegations of civilian casualties seriously and a formal Civilian Casualty Credibility Assessment had been opened to determine the facts surrounding this strike and the validity of the allegation of civilian casualties."Our goal has always been for zero civilian casualties, but the coalition will not abandon our commitment to our Iraqi partners because of [Daesh]'s inhuman tactics terrorizing civilians, using human shields, and fighting from protected sites such as schools, hospitals, religious sites and civilian neighborhoods," the coalition said.What happened in the incident on March 17 in Mosul al-Jadida district is still unclear. Some residents say a coalition air strike hit an explosive-filled truck, detonating a blast that collapsed buildings packed with families.U.S. military officials say they are investigating, but initial reports from residents and Iraqi officials in the past week said dozens of people had been killed after air strikes by U.S.-led coalition forces.Mosul municipality chief, Abdul Sattar al-Habbo, who is supervising the rescue, said 240 bodies had been pulled from the rubble of collapsed buildings. Previous estimates from local officials had said around 130 people had died.The United Nations also expressed its profound concern, saying it was "stunned by this terrible loss of life."The offensive to drive Daesh out of Mosul, now in its sixth month, has recaptured the entire eastern side of Mosul and about half of the west. But advances have stuttered in the last two weeks as fighting enters the alleys of the Old City, home to the al-Nuri mosque where Daesh leader Abu Bakr al-Baghdadi declared a caliphate spanning large areas of Iraq and Syria in 2014.The Iraqi Observatory for Human Rights said that since the campaign on western Mosul began on Feb. 19, unconfirmed reports said nearly 700 civilians had been killed by government and coalition air strikes or Daesh actions.Western Mosul contains the old city center, with its ancient souks, the Grand Mosque and most government administrative buildings. It was from the pulpit of the Grand Mosque that Daesh leader Abu Bakr al-Baghdadi declared a self-styled "caliphate" over parts of Syria and Iraq in 2014. The city, Iraq's second biggest, is the largest urban center captured by Daesh in both countries and its de facto capital in Iraq. Daesh was thought to have up to 6,000 militants in Mosul when the government's offensive started in mid-October. Of those, more than 1,000 have been killed, according to Iraqi estimates.