An oil tanker was hit by three rocket-propelled grenades fired from militants in skiffs last week in a little-reported incident, which took place near where U.S warships came under fire from Yemen-based Houthi militants last year, Navy officials told USNI News on Tuesday.

The Marshall Islands-flagged crude tanker M/V Muskie was hit by the RPGs from two skiffs as it transited through the Bab el-Mandeb Strait on May 31 entering the Red Sea, an official told USNI News.

“The vessel’s master reported that his vessel was fired upon by three rocket-propelled grenades, before the assailants broke off the attack,” reads a statement from the European Union Naval Force.

Maritime news service Splash24/7 reported the ship suffered damage to the superstructure before moving away from the scene. As of Tuesday, Muskie was operating in the Red Sea off the coast of Saudi Arabia.

“EU NAVFOR has not received any information that confirms that piracy-related tripwires/equipment were observed during the attack,” spokesperson Cmdr. Jacqui Sherriff said in the May 31 statement by EU NAVFOR.

“This indicates that the incident is more probably related to the continuing instability at sea off the coast of Yemen.”

While there’s no definitive evidence, U.S. officials suspect Houthi rebels in the attack on Muskie.

The attack is near where Houthi rebels fired on U.S. warships operating near the Bab el-Mandeb with anti-ship cruise missiles believed to be supplied by Iran, in an incident that took place in October.

Houthi rebels also attacked a United Arab Emirates-leased transport vessel and Royal Saudi Navy frigate operating in the Red Sea with a bomb-laden remote-controlled boat.

Since the attacks on the U.S. ships last year, the Navy has maintained an almost-constant presence in the region with a U.S. guided-missile destroyer and cruiser on station near the Bab el-Mandeb.