(CNN) -- Women in Somalia's third-largest city, Baidoa, have been ordered to wear Islamic dress starting this week or face jail time, according to a resident and Somali media reports.
Somali women wait to get medicine at a clinic near Mogadishu in July.
The order -- issued last week by Al-Shabaab, the radical Islamist militia that controls the city -- also warns business owners to close their shops during daily prayers, or they will be temporarily shut down, a local journalist said.
The militia has ordered women to cover their bodies and heads from view, according to a resident of Baidoa who did not want to be identified for security reasons. The clothing must be black, red or white, and women in the impoverished city are concerned that they will not be able to purchase clothing that conforms to the order, the resident said.
He said women would be jailed if they violated the order after it goes into effect Tuesday. Somalia's Shabelle Media, quoting an Al-Shabaab spokesman, said they would spend 12 hours in jail.
Shabelle points out that it is unclear how Al-Shabaab will enforce its order in Baidoa. The militia has issued similar edicts that failed to be carried out, according to Shabelle.
But this edict could be bolstered by Somalia's parliament, which voted unanimously Saturday to allow sharia, or Islamic law, in the Horn of Africa country. Lawmakers hope to boost President Sharif Ahmed's efforts to defeat Al-Shabaab, which has vowed to fight the government until sharia is imposed in Somalia.
Somali Prime Minister Omar Abdirashid Ali Sharmarke told Voice of America that parliament's vote "removed any justifications for any opposition group ... to use Islam for political ends."
There are concerns that Islamic law, which has numerous interpretations and variations, could lead to government-sanctioned human rights abuses in Somalia. The strict interpretation of sharia forbids girls from attending school, requires veils for women and beards for men, and bans music and television.
Last week, Al-Shabaab fighters patrolling the streets shot and killed a 20-year-old Somali man because he was not praying at the designated time, according to a local journalist who cannot be named for security reasons.
Sharmarke denied that the vote would open the door for a radical interpretation of Islamic law, such as that carried out by the Taliban in Afghanistan.
"People always think of the Taliban and Talibanization of a country. But that isn't the case," the prime minister said. "I think sharia in Somalia is part of the laws for thousands of years, and we never had this kind of a thing. Besides, it doesn't have to be that way, cutting hands."
Under some strict interpretations of sharia, a thief is punished by having a hand cut off.
Al-Shabaab was once the armed wing of the Islamic Courts Union, which took over most of southern Somalia in the second half of 2006. The United States says the group is affiliated with the al Qaeda terrorist network, and it backed an Ethiopian invasion that drove the ICU from power in 2006.
CNN's Ben Brumfield and journalist Mohamed Amiin Adow contributed to this report
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