|The “black flag of jihad” as used by various Islamic terrorist organizations (since the late 1990s) (Photo credit: Wikipedia)|
Several small explosive devices were also set off at the Air Products factory in Saint-Quentin-Fallavier, sources said.
The alleged attacker is said to have been carrying an Islamist flag, which was found nearby.
A man has been arrested, officials say.
The attack occurred around 10:00 local time (08:00 GMT), according to local media.
French Prime Minister Manuel Valls has ordered that security be stepped up at sensitive sites around Lyon.
The attack comes nearly six months after Islamist attacks in and around Paris that killed 17 people.