Pakistan's Musharraf barred from May polls
Pakistan's former military leader Pervez Musharraf has been barred from standing in general elections in May.
An election tribunal disqualified him from running in Chitral in the north-west. Earlier, he failed in an attempt to stand in three other seats.
Mr Musharraf's lawyer says he plans to file an appeal with the Supreme Court.
Meanwhile, at least four people were killed in an attack on a convoy of the main opposition PML-N party in the south-western province of Balochistan.
Pervez Musharraf returned from self-imposed exile in Dubai and London last month saying he wanted to save Pakistan, hoping to lead his All Pakistan Muslim League (APML) party into the general election next month.
On his return, Mr Musharraf submitted papers to contest the poll from Karachi, Islamabad, Kasur and Chitral.
While Mr Musharraf was given initial approval to run in Chitral, he was rejected in the remaining constituencies.
His opponents later filed an appeal against the decision to approve his candidacy in Chitral on the grounds that he had violated Pakistan's constitution when he imposed emergency rule in 2007.
The former general seized power in a military coup in 1999 and remained in office until 2008 when his supporters were defeated in parliamentary elections. Under threat of impeachment, he left the country.
He is already embroiled in a series of legal battles and has been attempting to stave off arrest and a bid to try him for treason.
He is facing a number of charges related to his time in office with court proceedings over the killing of Benazir Bhutto in 2007 and a tribal leader from Balochistan.
He has described the cases against him as "baseless" and politically motivated.
In addition to his legal and political woes, the Pakistani Taliban have vowed to target him with a squad of suicide bombers.
"His paper has been rejected by the high court. We will file an appeal in the Supreme Court," Mr Musharraf's lawyer Ahmed Raza Kasuri told AFP.
But after the tribunal's latest decision and if an appeal fails, Mr Musharraf will be ruled out of the running.
There was no immediate claim for the attack in Balochistan. Correspondents say the area where the attack took place has no Taliban presence and is known to be a hotbed of separatist rebel activity.
The BBC's M Ilyas Khan says that militant threats against secular politicians and parties, such as the ruling PPP and ANP, are hampering their election campaigns.
The brother, son and nephew of the leader of the PML-N party, Sardar Sanaullah Zehri, were killed in the bomb attack in Kuzdar in Balochistan, according to officials.
Mr Zehri narrowly escaped an earlier IED attack in Kalat area of Balochistan in October 2011. The attack was claimed by an armed separatist group, the Balochistan Liberation Front (BLF).
Most election violence in Pakistan takes place in the north-west of the country and secular parties such as the ANP, in power in Khyber Pakhtunkhwa province, and the ruling PPP have borne the brunt of such attacks.