AP PHOTO Counter-protestors stand behind barricades across the street from an anti-Islamic law protest rally Saturday, in Seattle.

SEATTLE — Demonstrators at small but raucous gatherings around the country Saturday raised the specter that extremist interpretations of Islamic law might somehow spread across the U.S., but many of the rallies drew even more boisterous counter-protests by people who called such fears unfounded.

Hundreds of counter-protesters marched through downtown Seattle, banging drums, cymbals and cowbells behind a large sign saying “Seattle stands with our Muslim neighbors.” Participants chanted “No hate, no fear, Muslims are welcome here” on their way to City Hall, where dozens of anti-Shariah protesters rallied.

A phalanx of bicycle police officers kept the sides separated during the sanctioned events, but authorities said a large fight broke out after the gatherings concluded. Police used tear gas to disperse rowdy demonstrators and arrested three people for obstructing law enforcement.