Prosecutors are asking for a sentence of life in prison for an alleged Islamic extremist who has admitted killing two U.S. airmen at Frankfurt airport last year, AP reports.

Dapd news agency reported that Prosecutor Jochen Weingarten told the Frankfurt state court in closing arguments Monday that Arid Uka deserved the maximum possible sentence due to the brutal nature of the crime.

The 21-year-old ethnic Albanian from Kosovo confessed as the trial opened to killing two men at point-blank range before wounding two more airmen and taking aim at a third before his gun misfired.

Under German law the court still has to review all the evidence despite the confession.

A verdict is expected on Jan. 19.