Foreign Ministry spokesman, Mohammad-Ali Hosseini said on Monday that the terrorists who opened fire on Iranian diplomats motorcade in Baghdad have not been identified yet, reported IRNA.
Hosseini told reporters that Iran's Embassy in Baghdad is following up the case through the help of Iraqi officials.
Three Iranian diplomats and one local staffer of Embassy in Baghdad were wounded in an assassination bid on May 15.
US agents opened fire at their motorcade at the diplomatic compound on northern neighborhood of Baghdad.
Hosseini reiterated that the terror attack on Iranian diplomats aims to damage Tehran-Baghdad friendly and brotherly relations.
Iran said on Saturday that it will not withhold support for the government of Prime Minister Nouri al-Maliki despite the Thursday's terror attack on Iranian diplomats in Baghdad.
Iranian Embassy in Baghdad said in a statement that the Iraqi security officials promised to arrest those involved in the terrorist operation and hand them over to Iraqi judiciary officials.
"Such cowardly terrorist attacks cannot stop Iranian diplomats from carrying out their duties as this is not the first time that diplomats and the staff of Iran's Embassy in Baghdad were subject to such terrorist acts," said the statement.
It said that perpetrators of such terrorist attacks "are enemies of the two neighboring countries".