'Due to', 'owing to', 'on account of' and 'because of' are all very similar indeed. They are all prepositions used with noun phrases. They indicate that something happened as a result of something, or introduce the reason for something happening. It is often best to put these phrases at the beginning of a sentence and to put a comma after the cause. However, it is also possible to put these phrases in the middle of the sentence, after the result. If you do this, it is not usually necessary to include a comma.
Owing to the lack of political will, no action has been taken.
Due to the fact that the country is experiencing an economic downturn, it is unlikely that any investments will be made.
Because of the bad weather, the match was cancelled.
Because of the traffic jam I was late arriving.
I resigned on account of the fact that I was being bullied.
I moved to a new flat due to the fact that it was taking me more than an hour to get to work each morning.