An attack on Azerbaijan’s embassy in the Iranian capital Tehran has left one person dead and two others wounded.

The Azeri government said a security official died when a gunman opened fire at embassy grounds.

Local police have reported the arrest of a suspect and an investigation into the incident.

Azerbaijan’s president, Ilham Aliyev branded the attack against the diplomatic mission a “terrorist act” and “unacceptable” on Twitter.

Mr Aliyev also demanded a swift investigation and for the perpetrator to be punished.

The Azeri foreign ministry said “the attacker broke through the guard post, killing the head of security with a Kalashnikov assault rifle”.

Jeyhun Bayramov, the country’s Minister of Foreign Affairs, condemned “the treacherous terrorist attack” and offered the government’s condolences to the family and relatives of the deceased officer.

They ministry also confirmed that the two other wounded guards were in a “satisfactory” condition and that it would evacuate embassy staff from the Iranian capital back to Azerbaijan.

Tehran’s police chief, General Hossein Rahimi, told the Iranian Tasnim news agency that Friday’s attack may have been motivated by “personal issues”.

He later told the state-owned Press TV that the assailant – whose wife is reportedly an Azeri citizen – had waited outside the embassy before ramming his car into the back of a vehicle belonging to a member of the diplomatic mission and then opening fire with his AK-47 rifle.

“He claims his wife has been held at the embassy for nine months,” General Rahimi said.

In a strongly worded Azeri government statement the foreign ministry highlighted previous threats to diplomatic staff and attempts to raise the issue with Iranian authorities.