Advocates for immigrants demanded an investigation into a series of immigration raids last month that they said left at least six Guatemalan men bloodied and bruised. Immigration and Customs Enforcement denied all accusations of misconduct by agents in the raids on Nov. 19 in three South Florida counties, noting that the operation netted seven people charged with sex trafficking, and led to the release of several women. But lawyers working with other detainees said they were concerned that the agency was using human trafficking laws as a front for broader operations, and a cover for harsh tactics. “There is a way that these operations should be conducted,” said Jose Rodriguez, a lawyer with the American Civil Liberties Union of Miami-Dade County. “And this is not it.” At a news conference, Mr. Rodriguez and others said immigration agents had relied on vaguely worded warrants to invade people’s homes and arrest nearly anyone who looked Hispanic. In all, according to the imm