Pakistan's former military ruler Pervez Musharraf, who is on trial for treason, narrowly escaped what police called an assassination attempt as a roadside bomb went off shortly before his convoy was due to pass early Thursday.
The bomb was planted on Musharraf's route from an army hospital in Rawalpindi, where he has been staying since January, to his home on the outskirts of Islamabad. It went off at around 2:00 am (2100 GMT Wednesday).
Nobody was injured and there have so far been no claims of responsibility.
"Four kilograms (nine pounds) of explosive device planted in a pipeline under a bridge exploded around 20 minutes before the former president was supposed to cross the spot," senior police official Liaqat Niazi said.
The blast occurred at the Faizabad interchange, which lies at the boundary of the two cities, and destroyed a footpath around two metres (seven feet) wide.
Niazi said Musharraf was then taken home via an alternative route.
Muhammad Naeem, a spokesman for the Islamabad police, confirmed the incident, saying a bomb disposal squad had cordoned off the area after the blast and searched for additional explosives.
"Nobody was injured in the blast," he said, adding Musharraf was the intended target.
Musharraf, who led Pakistan from 1999 to 2008, returned from self-imposed exile in March last year to fight in general elections, but was barred from taking part and has faced a series of legal cases including treason.
The Taliban have also vowed to send a squad of suicide bombers to kill him, and security threats have prevented Musharraf from appearing at all but two of his treason hearings.
It was the fourth apparent attempt on the ex-general's life, with the first three occurring while he was in office.
Prior to his hospitalisation in January for a heart condition, several small bombs were discovered by officials near his villa, with some unconnected to detonators.
Some commentators in the Pakistani media said those bombs may have been deliberately planted by his own team in order to exaggerate the threat to Musharraf's life and expedite his safe passage out of the country.
- No deal, yet -
On Monday, a special court indicted Musharraf for treason, in what was seen as a milestone for civilian authority in a country long dominated by the army.
The charges relate to Musharraf's 2007 imposition of emergency rule which came as the Supreme Court was due to rule on the validity of his re-election as president.
Treason carries the maximum penalty of death, but some analysts were sceptical of whether the government would allow the trial to be seen through to its completion and risk a greater clash with the military.
Musharraf had also sought permission to leave the country to see his ailing mother in the United Arab Emirates, leading to renewed speculation that a deal, which would allow all sides to save face, was imminent.
But the government on Wednesday refused to end a travel ban preventing Musharraf from leaving the country.
"The interior ministry has sent a written reply to Musharraf refusing to lift travel bans as there are a number of cases against him," an official of the interior ministry told AFP.
Musharraf had been staying at the Armed Forces Institute of Cardiology (AFIC) in the garrison city of Rawalpindi since being taken ill with a heart condition in January.
But he was believed to be keen to return to his comfortable villa in the scenic Bani Gala suburb of Islamabad.
Ahmad Raza Kasuri, a member of his legal team, told reporters that Musharraf had discharged himself.
"He left the AFIC at his own request and was with his son Bilal," he said.
Thursday's attack had echoes of the first major attempt on Musharraf's life in December 2003, when a powerful bomb went off minutes after his highly guarded convoy crossed a bridge in Rawalpindi.
A few days later, he survived another attempt by two suicide bombers which left 16 people dead.
In July 2007, an unknown group fired a 7.62 submachine gun at Musharraf's plane as it took off from a runway in Rawalpindi.