Militia forces in Misurata were among those who refused to surrender weapons as requested by the interim Transitional National Council in December. Human Rights Watch estimates there are more than 200 militias in Misurata.
Shashank Joshi, a research fellow at London's Royal United Services Institute, told Bloomberg News it's unlikely the militias would threaten Libyan unity, however.
"Rather than tearing Libya apart, it is more likely to lead to a dysfunctional government, a government that is hobbled by incapabilities because it has been so subverted and hollowed out by regional interests," he said.
Amnesty International, however, said many of the militias in post-revolution Libya were operating outside the law.
Residents in Misurata had the country's first election since Moammar Gadhafi's government fell last year. Elections were contested for the 28-seat local council in the first democratic election in Libya in roughly 40 years.
Doctors Without Borders announced in January they were halting work in Misurata because of detainee abuse.