The bomb detonated near his private home. The minister said the explosion took place just after visitors to his house had left by car. Three of the guests were injured.
"It was a remote-controlled device planted under a billboard near my house," Jan told AFP by telephone.
"Perhaps those responsible thought I was in the car."
Senior police officer Mohammad Ejaz told AFP, "We have rushed teams to find out details. Initial reports say that three people were wounded."
The minister belongs to the secular Awami National Party (ANP) whose leaders have in the past been the targets of militant attacks. Sunday’s blast was the first since US navy commandos killed Al-Qaeda leader Osama bin Laden in a covert operation in Pakistan a week ago.