AQABA, Jordan (AP) — Jordan on Tuesday promised an investigation into the deadly explosion of a chlorine tank on Monday at the Red Sea port of Aqaba, which killed at least 13 people.

A crane loading chlorine tanks onto a ship dropped one of them, releasing a large plume of toxic yellow smoke. Along with those killed, some 250 were sickened, authorities said.

King Abdullah II “stressed the need to provide transparent explanations to the public after investigations conclude, as well as identifying shortcomings and holding those responsible to account by law,” the palace said in a statement. He also offered condolences to victims’ families.

Prime Minister Bisher al-Khasawneh visited the site Tuesday and, citing civil defense and environmental authorities, said the gas concentration in the area had returned to normal. He said that most movement at the port has resumed, except for the exact site of the incident which was being cleaned and inspected.

Al-Khasawneh said many of those in hospitals were being discharged.

A government spokesman, Faisal Al-Shboul, told state media that eight of the dead were Jordanian and five were foreigners. Among the injured were Chinese and Vietnamese nationals, hospital officials said.

Video carried on state TV showed the moment the tank exploded, sending dockworkers scrambling to escape the toxic cloud. Some 200 people were hospitalised.

The Public Security Directorate, which initially described it as a gas leak, said authorities sealed off the area after evacuating the injured and sent specialists in to address the situation.

State-run Jordan TV said 13 people were killed. Al-Mamlaka TV, another official outlet, said 199 were still being treated in hospitals. The Public Security Directorate said a total of 251 people were injured.

Aqaba is on the northern tip of the Red Sea, next to the Israeli city of Eilat, which is just across the border. Both are popular beach and diving destinations.

Eilat’s emergency services said in a statement that there was no impact on the city but that they were following the situation closely.