Former Pakistani president Pervez Musharraf is en route to his homeland after more than four years in self-exile.
Mr Musharraf's flight to Karachi left Dubai carrying supporters who hope the ex-general can make a political comeback in May's parliamentary elections.
But he faces significant risks, as he is considered an enemy of Islamic militants for siding with America in the response to the September 11, 2001 terrorist attacks. The Pakistan Taliban has vowed to kill him.
He also faces charges linked to the probe into the 2007 assassination of former prime minister Benazir Bhutto.
Mr Musharraf took power in a 1999 coup and was forced to step down in 2008 amid growing discontent over his rule. He has since lived in Dubai and London.
The flight from Dubai came after several failed promises to return in recent years. Mr Musharraf announced in early March that he would lead his party, the All Pakistan Muslim League, in May elections.
Mr Musharraf met briefly with reporters in Dubai before heading to the airport wearing a white shalwar kameez - the traditional loose-fitting outfit in Pakistan - and sandals from the country's Peshawar region near the Afghan border.
His decision to return was given a boost last week when a Pakistan court granted him pre-emptive bail - essentially preventing his immediate arrest - in three cases in which he is implicated, including Ms Bhutto's death. He now has 10 days to appear in court. He has dismissed the various charges as baseless.
The Pakistan Taliban has released a video threatening to unleash suicide bombers and snipers against Mr Musharraf. He had been expected to address supporters in Karachi but police have cancelled his permit because of a "very serious threat," said Tahir Naveed, the deputy inspector general of Karachi police.
He said Mr Musharraf would be provided with an armoured vehicle to protect him due to the threats. Banners and billboards welcoming Mr Musharraf back to Pakistan lined the street from the airport where he is expected to land.