Leverkusen explosion: hope fades of finding Chempark missing five

Two people already confirmed dead from Tuesday's blast at German chemical park

The five people still missing a day after a huge explosion at a German chemical park are unlikely to be found alive, the site operator said on Wednesday, urging residents not to touch possibly toxic soot from the blast.

Two people were already confirmed dead in the incident on Tuesday which also injured 31 others.

“We have no hope of finding the missing alive,” said Frank Hyldmar, chief executive of Chempark operator Currenta. “Our thoughts are with the families.”

The cause of the Tuesday morning blast at Chempark's waste incineration site in the western city of Leverkusen remains unknown, he told a press conference.

The explosion, which was heard several kilometres away and rattled the windows of nearby homes, sent a cloud of black smoke into the air.

The blast also triggered a fire in storage tanks for solvents that took firefighters hours to extinguish.

A report in Der Spiegel magazine said the blast was measured as far as 40 kilometres away.

Police closed several motorways in the area and residents were told to stay indoors and shut their windows amid concerns dangerous gases may have been released.

The warning remained in place for most of Tuesday until city authorities said air pollution measurements had shown no abnormalities.

Leverkusen locals advised to avoid 'toxic' soot

Experts are still investigating whether soot particles that came down after the blast may be toxic, with a final report not expected for several days.

Currenta's chief operating officer Hans Gennen told residents not to touch any residue they might come across and to contact the authorities so samples can be taken.

Local people have also been advised not to eat fruit or vegetables from their gardens, and playgrounds in Leverkusen's Buerrig and Opladen neighbourhoods are temporarily closed.

“We will do everything we can to get to the bottom of this terrible event,” Currenta's Mr Hyldmar said.

An onlooker watches as smoke rises from the Chempark blast which reportedly was felt up to 40 kilometres away. AFP

Four of the missing are Currenta employees, while the fifth works for an external company, he said.

Of the 31 injured, one is in a serious condition.

All of those affected worked at the chemical park.

The area where the blast happened, in Leverkusen's Buerrig district, is a short distance away from Chempark's main industrial park that houses numerous chemical companies, including Bayer, Lanxess and Evonik Industries.