This is a Still from the Bitmac factory in Naxxar that operates at night time with cancerous asphalt fumes escaping its factory.

Why work at night?

At night its harder to see the smog, smoke and cancerous fumes that escape the factory. 

Do the government, police, authorities know about it?

Oh yes. But they turn a blind eye as they will to the Maghtab incinerator. Nothing works in this country, least of all enforcement and monitoring. Don't trust them!

Video is available of these illegalities and has been with the police for ages.