Pakistan's government has charged bin Laden's three widows with illegally entering and staying in the country, Interior Minister Rehman Malik said on Thursday.
"If the family of Osama bin Laden is not released as soon as possible, we will attack the judges, the lawyers and the security officials involved in their trial," Ehsanullah Ehsan of the Tehrik-e-Taliban Pakistan (TTP) told Reuters.
"We will carry out suicide bombings against security forces and the government across the country."
Mr Malik did not specify which court was dealing with the case. The three women will have to stand trial, but it was not clear what punishment they face if convicted.
Bin Laden was killed in a secret U.S. raid in the northern Pakistani garrison town of Abbottabad in May last year.
The al Qaeda leader's body was flown out by American special forces, but his three wives and an undisclosed number of children were among the 16 people detained by Pakistani authorities after the raid.
Two of the wives are Saudi nationals, and one is from Yemen, according to the Pakistani foreign ministry.
Pakistan had previously said that it would repatriate the women after a government commission probing the bin Laden raid had completed its questioning.
The commission has interviewed the family members for clues about how the al Qaeda chief managed to stay in the country undetected.
The TTP vowed revenge after bin Laden's death last year, and carried out high-profile attacks across Pakistan. It bombed an American consulate convoy, laid siege to a naval base and killed paramilitary cadets.
Formed in 2007, the TTP is an umbrella group of various Pakistani militant factions operating in Pakistan's unruly northwestern tribal areas along the porous border with Afghanistan.
TTP's spokesman also threatened attacks against Shad Begum, a women's rights activist based in the northwestern city of Peshawar.
The U.S. State Department honoured Begum with the 2012 International Women of Courage award at a ceremony in Washington on Thursday.
"She works for a secular and infidel system in Pakistan," Ehsan said. "That is why America has given her this prize."
Copyright Thomson Reuters 2012