A 33-year-old Moroccan has gone on trial in Duesseldorf on allegations that he sexually assaulted a woman on New Year's Eve, one of a string of attacks that night blamed largely on foreigners that fueled a nationwide debate over immigration policies.

The defendant, identified only as Toufik M., is accused of being part of a group of 15-20 men who surrounded the woman and groped her.

News agency dpa reported Monday that this is the first sexual assault case related to New Year's Eve attacks to go to trial. Most attcks are alleged to have occurred in Cologne, about 50 kilometers (30 miles) south of Duesseldorf.

Cologne authorities have received more than 1,500 criminal complaints, about a third alleging sexual crimes. One man has been charged there with sexual assault.