Tasnim � Iran �deeply regrets� the unintentional downing of a Ukrainian plane this week, President Hassan Rouhani said on Saturday.

�Armed Forces� internal investigation has concluded that regrettably missiles fired due to human error caused the horrific crash of the Ukrainian plane & death of 176 innocent people. Investigations continue to identify & prosecute this great tragedy & unforgivable mistake,� Rouhani said in a tweet on Saturday.

In a follow-up tweet, he added, �The Islamic Republic of Iran deeply regrets this disastrous mistake. My thoughts and prayers go to all the mourning families. I offer my sincerest condolences�.

The General Staff of the Armed Forces of the Islamic Republic of Iran said in a statement earlier in the day that the country�s military �unintentionally� shot down the passenger jet after it flew close to a sensitive site.

Those responsible would be held accountable, the statement said.

The victims of Wednesday�s crash included 82 Iranians, 63 Canadians, 11 Ukrainians, 10 Swedes, four Afghans, three Germans, and three British nationals.

All 179 people on board the Boeing 737, including nine crew, were killed when the jetliner crashed shortly after takeoff from the airport on Wednesday morning.

The plane operated by Ukraine International Airlines (UIA) was bound for Kiev.