President Hamid Karzai has condemned Monday's separate bombings in Afghanistan's southern Zabul province and in the US city of Boston in two statements released Tuesday.
Karzai expressed his condolences to the victims of the two unrelated bombings which he condemned as acts of terror against civilians.
The roadside bomb in Zabul province killed seven members of the one family and injured four others Monday morning when their "trailer tractor" hit the makeshift bomb hidden in the road.
"Condemning it in the strongest possible terms, President Karzai described the act of planting bombs on public routes, as crimes committed by mercenaries on orders by their foreign masters against Islam and Afghan values," the statement from Karzai's office said.
"The President offers heart-felt condolences and sympathies to the close relatives of the victims, wishes for their endurance and prays for quick recovery of the wounded, It added.
Meanwhile, twin bombs in the US in a crowded spectator area for a marathon in Boston city has killed three people and wounded at least 100 more Monday, US time.
"Denouncing the terrorist attacks in the strongest possible terms, President Karzai said, "Having suffered from terrorist attacks and civilian casualties for years, our people feel better the pain and suffering arising from such incidents," the statement from his office said Tuesday.
"President Karzai offers condolences and sympathies to the families of the victims and the people of the United States of America," it added.
The Pakistani Taliban has denied any involvement in the attacks, according to Reuters report.
US President Barack Obama went on national television to say it was not yet clear who was behind the blasts.
"We still do not know who did this or why. And people shouldn't jump to conclusions before we have all the facts," Obama said. "But make no mistake, we will get to the bottom of this, and we will find out who did this, we'll find out why they did this."
However, other US officials have described the act was an act of "terror" and done by "terrorists".