SAN FRANCISCO—It should have been a festive occasion for House Speaker Nancy Pelosi, but the ribbon-cutting of a new federal building turned into a skirmish with anti-war protesters.

About a dozen people chanted "Impeach now!" as Pelosi spoke at the dedication of the $144 million, 18-story landmark office complex, which boasts cutting-edge energy efficiency features. The demonstrators also unfurled a large "impeach" banner

a Bush administration official fired back at the demonstrators, accusing them of not paying taxes.

It would be hard to describe a situation worse than what President Bush has gotten us into there," Pelosi said.

"We have to do more," she said.

Pelosi ignored a question about Cindy Sheehan, an anti-war activist and mother of a slain soldier who has decided to challenge Pelosi for her congressional seat unless she moves to impeach Bush.