The decision not to renew Blackwater Worldwide’s security contract in Iraq when it expires in early May has left the State Department scrambling to fill a protection gap for U.S. diplomats and civilian officials there.

Two other U.S. security contractors with a far smaller presence in Iraq — DynCorp International and Triple Canopy — have been asked to replace the ousted company, according to State Department and company officials. To meet time, training and security-clearance pressures, officials said, one or both of the firms are likely to undertake the task by rehiring some personnel now working for Blackwater.

The Iraqi government refused to issue Blackwater a license to perform security services after a 2007 incident in which company guards on a diplomatic protection mission shot and killed 17 civilians in Baghdad. U.S. prosecutors have indicted five of the guards on charges of manslaughter. Blackwater (which recently changed its name to Xe) still has State Department contracts for air transport in Iraq and security for U.S. diplomats in Afghanistan.