The BBC's Owen Bennett-Jones reports: "Military authorities had come under increasing pressure to do something"

The charges are linked to the 12 October episode in which an airliner carrying army chief-of-staff General Pervez Musharraf and nearly 200 other people was refused landing rights in Karachi.

General Musharraf staged a military coup on that day after Mr Sharif fired him and tried to install a junior general as the new military chief.

The ousted prime minister was taken into custody, where he remains.

Ministers of Mr Sharif's party, the Pakistan Muslim League, said they would meet on Thursday and might then issue a formal statement about the military's decision to charge the former prime minister.

The complaint - lodged at the Karachi Airport police station - marks the first step towards formal charges being brought against the accused in a court.

The BBC's Owen Bennett-Jones in Islamabad says a formal police investigation will now begin, and it is likely that at a later stage charges will be framed in court.

News of the charges against the former prime minister came on the same day that his Pakstan Muslim League announced that it would challenge the suspension of the country's constitution in the Supreme Court.

'Attempted assassination'

The police complaint relates to the drama played out in the sky over Karachi airport on 12 October, when General Musharraf's plane was denied permission to land.

The BBC's Zaffar Abbas reports from Islamabad

General Musharraf has said previously that the pilot of the Pakistan International Airlines plane circled the airport awaiting instructions, while fuel ran dangerously low and the aircraft was redirected to the interior Sindh city of Nawabshah.

The military took control of Karachi airport while the plane was aloft

Mr Sharif had reportedly despatched his security team to Nawabshah to take General Musharraf into custody, after sacking him.

But while the plane was en route to Nawabshah, the army staged a coup, seized control of Karachi airport, and ordered the aircraft to land there instead.

General Musharraf said that when the aircraft finally touched down, it had only seven minutes of fuel left on board.

The general accused Mr Sharif at the time of an attempted assassination and of endangering the lives of the more than 200 passengers and crew on board.

Accused

The complaint, filed by Lieutenant Colonel Attiq Uzaman Kiyani on behalf of the new military government, accuses eight other current and former officials.

The other accused are:

• Mr Sharif's former adviser on southern Sindh affairs, Ghaus Ali Shah
• the former managing director of Pakistan's International Airlines, Shahid Haqqan Abbasi
• former Sindh police Inspector General Rana Maqbool
• the former director general of the Civil Aviation Authority, Aminuddin Chaudhry
• Karachi police chief Akbar Ara Im
• three other police officials.

Police said Mr Sharif and the eight other accused had been taken into protective custody and interrogated by a team of investigators.

Mr Sharif is reported to be kept under tight security and has not been allowed to speak publicly since the military took power.

US concern

General Musharraf has promised a clean, accountable administration

In Washington, the Clinton administration appealed for the protection of the legal rights of the accused.

State Department spokesman James Foley said the administration renewed its call that Mr Sharif "and all the other detainees be accorded all their rights under the law and due process".

Correspondents say the military had been coming under increasing pressure to do something about the deposed prime minister.

Since he was detained almost one month ago, Mr Sharif's family and human rights activists have been calling on the authorities either to release or to charge him.