WASHINGTON (Reuters) - The man who tried to assassinate former President Donald Trump on Saturday was spotted by law enforcement nearly 30 minutes before shots were fired, a local NBC affiliate reported on Monday.

WPXI reported that a member of Beaver County, Pennsylvania's emergency services unit noticed a suspicious man on a roof near the rally at 5:45 p.m., called it in and took a picture of the person.

Shots were fired at the rally in Butler, Pennsylvania, after 6 p.m.

(Reporting by Jasper Ward)