Two Katyusha rocket attacks targeted an Iraqi military base in Mosul and foreign oil companies in the southern province of Basra, security sources confirmed on Wednesday.

Axar.az reports citing foreign media that, in what appears to be yet another addition to a series of attacks on military bases in Iraq where US troops are stationed, a Katyusha rocket on Tuesday night landed near one such site north of Mosul, with the launch pad discovered shortly after.

The “locally-made” missile was fired across the Tigris River and landed in an open area in a base in the west bank of the city but claimed no casualties, Nineveh Operations Command director, Nu’man al-Zubei’I, said in a statement following the incident. He gave no further details.

Security sources told local media that the attack was carried out using Katyusha rockets which landed on the Presidential Palace of Mosul—a residential complex of former dictator Saddam Hussein— currently used as a US-Iraqi military training compound, hosting US instructors.

Local outlets also published pictures they purported were of the launch pad used in the attack. In the pictures, Iraqi military personnel can be seen inspecting the site along with a large launch pad in an undisclosed area.

Iraq’s Security Media Cell in a statement noted the rocket landed near the Nineveh Operation Command’s headquarters, without causing any serious damages or casualties.

On Wednesday early morning, another Katyusha rocket hit the site of the residential and operations headquarters of several global major oil firms, including US giant Exxon Mobil, near Iraq’s southern city of Basra, injuring three people.

The Basra incident came soon after the recent return of Exxon Mobil staff to the city, who had been evacuated over security concerns and warnings issued by the US State Department last month.

In response to the rocket attack in Basra, Exxon Mobil has evacuated 21 foreign staff immediately by plane to Dubai, a security source told Reuters.

There was no immediate claim of responsibility for the two attacks.

This marks a series of such incidents with the latest two occurring a day after the other amid heightened tensions between the US and Iran, which supports Shia militias under the Hashd al-Shaabi umbrella organization, also known as the Popular Mobilization Forces (PMF), who have been vocal in disapproving of the US’ presence in Iraq.

The previous two attacks targeted airbases north of the capital of Baghdad, with the farthest being about sixty kilometers away from the city. Neither has caused any casualties, Iraqi military officials have said, and no one has yet claimed responsibility for the aggression.

Tensions between Washington and Tehran have reached all-time highs a year after the US withdrew from the 2015 nuclear agreement between Iran and major world powers and imposed multiple rounds of sanctions that have severely limited Iran’s capacity for trade, notably its oil exports.