As the lights went out at Candlestick Park before and during Monday night's San Francisco 49ers game, police were also concerned with a threat of an explosive device, according to the San Jose Mercury News.
The SFPD told the Merc that just before kick-off they got a call that was a bomb threat. Police fanned out, found no credible threat, and the game was not affected.
The game was initially delayed due to what is apparently a blown transformer near the stadium. ESPN cameras caught a bright, blue-ish explosion as they took an aerial, pre-game shot of the field.
The 49ers defeated the Pittsburgh Steelers 20-3.