LONDON, July 23 (Xinhua) -- Renewed attacks on international shipping in the Red Sea region are "indefensible" and threaten seafarers' lives, maritime trade security and global supply chains, International Maritime Organization (IMO) Secretary-General Arsenio Dominguez said Thursday.

"I unequivocally condemn the latest reported attacks on international shipping in the Red Sea area. These attacks are indefensible," Dominguez said in a statement.

He stressed that seafarers are civilians performing essential work that supports economies and communities worldwide, and urged ship operators to "thoroughly assess risks" before transiting the region.

"Seafarers must never be placed in harm's way or targeted in situations of conflict or instability," he said.

Dominguez also renewed his call for the immediate and unconditional release of all seafarers still being held captive following piracy attacks in the Red Sea and Gulf of Aden region, saying their safety was "a fundamental obligation under international law and a shared responsibility of the global community."

"The Red Sea is a critical maritime corridor for international trade," he said, warning that continued attacks on shipping risked escalating tensions, further disrupting commercial routes and undermining freedom of navigation. "De-escalation is the only solution," Dominguez said.

He also expressed concern over potential pollution resulting from recent incidents in the Red Sea and earlier incidents in the Strait of Hormuz. "The IMO will continue to monitor the situation and stands ready to assist as necessary," he said.

The statement followed a series of attacks and security incidents involving commercial vessels in and around the Red Sea, renewing concerns over the safety of one of the world's key maritime trade routes.

A tanker caught fire off the coast of Saudi Arabia on Wednesday after being struck by an unknown projectile, according to the United Kingdom Maritime Trade Operations.

At around the same time, Yemen's Houthi group said it had carried out a military operation targeting two Saudi oil tankers in the Red Sea.

According to the IMO, more than 20 attempted or actual incidents of piracy and armed robbery against ships were recorded in the Red Sea and the Gulf of Aden in the three months to July 6, with increasingly dangerous weapons being used and violence against seafarers escalating. ■