After the Bears/Panthers football game ended, KTVU, the local San Jose Fox affiliate, reported that a "'Suspicious Object" had been found at SFO. Of the reports currently on Google News, this FoxReno report seems to have the most details:

SAN FRANCISCO -- A security checker in the American Airlines section of San Francisco International Airport Terminal 3 Sunday detected a 'suspicious object' on the x-ray machine, forcing the evacuation of the surrounding gates and delaying at least three flights.

SFO spokesman Mike McCarron said the incident began at 12:49 p.m. and quickly was elevated from the supervisor to the police to the bomb squad.

The entire terminal was not evacuated, but Checkpoint E was closed down and the surrounding gates. The evacuation had impacted three American Airlines flights.

"As a result," McCarron said. "Most American Airlines flights have been impacted. We are moving approximately 300 people for the gate area."

The spokesman said that the person whose luggage contained the 'suspicious device' had been questioned, but was not a suspect. It was not known how long it would take before the gates and security points were reopened.

Update: More details here:

Part of a San Francisco International Airport terminal was evacuated for several hours Sunday after a suspicious item was found in a piece of luggage, officials said.

A baggage screener in the American Airlines section of Terminal 3 "noticed a suspicious item" in a passenger's carryon bag around 2 p.m., said airport spokesman Mike McCarron.

Authorities would not say what exactly was found in the bag, but San Francisco police Lt. Bill Darr said "there were items, articles inside the carryon luggage that did resemble components of a possible device."

Two men and a woman, all from South Carolina, were detained for questioning, authorities said. They were headed on a flight back to South Carolina through Dallas.

The immediate area around the security checkpoint was evacuated and at least three afternoon flights were delayed as a bomb squad investigated, McCarron said. Officers destroyed the bag with a water cannon.

The terminal fully reopened at 5 p.m.