Nearly an hour and a half of surveillance footage from the night of Laquan McDonald's death is missing from the security system at a Chicago Burger King near the scene of the black teen's alleged murder, and new evidence obtained by NBC Chicago suggests police may have been the last ones to view it.

Jay Darshane, district manager for the Burger King at Pulaski Road and 41st Street, told NBC Chicago in May that his cameras were fully operational when police came in on Oct. 20, 2014, the night of the shooting. While he wasn't at the restaurant at the time, he said he authorized the manager on duty to give the officers access to the footage. He suggested that the video wouldn't show the fatal 16 shots, but it might contain details about what happened directly before and after officer Jason Van Dyke killed McDonald.

The next day, however, Darshane discovered an 86-minute gap in the footage, from 9:13 p.m. to 10:39 p.m. Prosecutors say Van Dyke fired the first of 16 rounds at 9:57. Darshane -- who testified about the missing video before a federal grand jury earlier this year, according to the Chicago Tribune -- said he believes police deleted the key footage. But local law enforcement officials say they haven't found evidence that the security system was tampered with.

Now NBC Chicago has revealed the two screen grabs below, which appear to show at least one officer reviewing security recordings at Burger King on the night of McDonald's death.