The attack comes as Israeli ground forces entered Lebanon after days of Israeli airstrikes that killed Hezbollah leader Hassan Nasrallah and other top leaders and the earlier explosions of sabotaged electronic devices used by Hezbollah members. The Houthis had threatened “escalating military operations” targeting Israel on Monday after they apparently shot down a U.S. military drone flying over the country.

The attack Tuesday morning took place some 110 kilometers (70 miles) off the port city of Hodeida in the Red Sea, which has become a battlefield for shippers since the Houthis began their campaign targeting Israel-linked ships travelling through a waterway that once saw $1 trillion a year of cargo pass through it.

A captain on a ship saw four “splashes” near his vessel, the British military's United Kingdom Maritime Trade Operations centre said in a warning. That likely would have been missiles or drones launched at the vessel.

“All crew are safe and the vessel is proceeding to (its) next port of call,” the UKMTO said.

The Houthis did not immediately claim responsibility. However, they sometimes take hours or days to acknowledge such attacks.

Houthis have targeted more than 80 merchant vessels with missiles and drones since Israel's war on Gaza started in October. They have seized one vessel and sank two in the campaign that has also killed four sailors. Other missiles and drones have either been intercepted by a U.S.-led coalition in the Red Sea or failed to reach their targets, which have included Western military vessels.

The rebels maintain that they target ships linked to Israel, the U.S. or the United Kingdom to force an end to Israel’s brutal assault on Gaza. They have repeated that they would halt their offensive once a ceasefire is established in the Gaza Strip.

The last attack on a merchant ship by the Houthis came on Sept. 2.

The Houthis claimed an attack targeted American warships last week. The rebels fired more than a half dozen ballistic missiles and anti-ship cruise missiles and two drones at three U.S. ships that were travelling through the Bab el-Mandeb Strait, but all were intercepted by the Navy destroyers, a U.S. official said Friday. The official spoke on condition of anonymity to discuss details not yet publicly released.

The Houthis also continue to launch missiles targeting Israel, drawing a barrage of airstrikes from the Israelis this weekend on Hodeida.

*This story was edited by Ahram Online.