The head of a suspected chemical weapons' research centre in Syria has been killed in a car bombing, pro-government and opposition media report.
Aziz Asber was the head of a facility belonging to the government's Syrian Scientific Research Centre.
Western intelligence agents have said the organisation is linked to a Syrian chemical weapons programme.
A rebel group said it carried out the attack, but there has been speculation that others could be involved.
Asber and his driver both died when the car they were travelling in exploded late on Saturday, according to the UK-based monitor The Syrian Observatory for Human Rights.
The opposition Abu Amara Special Missions group claimed responsibility for the killings, which pro-government outlets described as an "assassination".
The research centre that Asber led in the western city of Masyaf has previously been targeted by air strikes. The Syrian government has blamed Israel for these attacks, including one that took place two weeks ago.
Syria has denied owning or using chemical weapons, but the US and the Syrian opposition accuse the government of carrying out a chemical attack on former opposition stronghold Douma near Damascus that reportedly killed 40 people in April this year.