OAKLAND, CALIF.—Anti-Wall Street demonstrators held vigils for an Iraq War veteran seriously injured during a protest clash with police in California as some occupy encampments came under growing pressure from authorities to abandon sites in parks and plazas. A crowd of at least 1,000 people, many holding candles, gathered Thursday night in Oakland in honour of 24-year-old Scott Olsen, who is hospitalized with a fractured skull. In Nashville, police cracked down overnight on an Occupy protest camp near the Capitol under a new policy setting a curfew for the complex. They moved in a little after 3 a.m. and arrested...