KARACHI Pakistan is warning that the Taliban are plotting to secure the freedom of Osama bin Ladens wives and children by kidnapping a high-ranking government official and then offering to exchange him or her for Al-Qaeda chiefs family, reported Fox News on Friday. US Navy seals killed bin Laden in a May helicopter-borne raid on his house in Abbottabad. They took the corpse with them, but left at least two of his wives and several children in the house. They were detained by Pakistani authorities. The Interior Ministry warned of the kidnap purported plot in a letter that was sent to top security officials on August 23 - just three days before gunmen seized Shahbaz Taseer, the son of slain Punjab Governor, Salmaan Taseer. Interior Minister Rehman Malik said there was no evidence that the group that had seized Shahbaz Taseer from the streets of Lahore was hoping to exchange him for bin Ladens family members. An American news agency reported obtained a copy of the letter, stamped 'secret on Friday. It said the information that led to the warning was reliable. It doesnt say which Pakistani official the Taliban plan to kidnap, but said the most likely location was one of the countrys four provincial capitals. Pakistan has reportedly released Taliban prisoners before in exchange for kidnapped government officials and army officers. Taseers kidnapping was the second high-profile abduction in Lahore in August. On Aug 15, gunmen seized a 70-year-old American aid expert from his house. The man, Warren Weinstein, is still missing, and police have declined to speculate on who may be holding him. Meanwhile, Pakistani police said they were preventing foreign journalists and other visitors from getting close to the house of bin Laden ahead of the 10th anniversary of the Sept 11 attacks. The Danish Ambassador to Pakistan and his wife, and two French journalists, were among several people detained this week in Abbottabad. They were held briefly before being allowed to return to Islamabad, police in the northern town said. Ambassador Uffe Wolffhechel said he asked security officers at a checkpoint on the road to the house whether he and his wife could get in viewing range of it and they said 'we are sorry, no, and we shook hands and said 'have a nice day. He said they were then held for around two hours while officers checked their papers.