Maal Hijrah or oftenly called Awal Muharram is the first month of the Islamic calendar, during which fighting is prohibited.
It's haram or forbidden for human kind to wage war against each other, killing or getting involved in any kind of confrontation.
So, it's unlawful to fight during this month.
However, I doubt it. In Malaysia, I am sorry to say that the spirit of Awal Muharram is not really observed, except for the public holiday.
Let's see who will break the 'rules'...
SELAMAT MAAL HIJRAH