SAN FRANCISCO (CBS SF) — Traffic in San Francisco’s South of Market district was a slow go Tuesday as an outage knocked out stoplights at several intersections, authorities said.

The intersections were turned into four-way stops while traffic officers manned others.

“Numerous traffic lights are malfunctioning in multiple locations throughout the city, including South of Market between 6th & Mission Streets & 13th & Market Streets; and Folsom & 6th Street down to Folsom & Hawthorn,” the San Francisco Department of Emergency Management tweeted shortly after noon.

San Francisco Muni officials said there will likely be minor delays on the N-Juday and T-Third muni rail lines.

Officials did not say what had caused the outage.