Two men are grateful to be alive -- after being rescued from a Northland island overnight

The pair's tinny experienced engine failure and then sank, while they were travelling between Mangawhai and the Hen and Chickens Islands.

They were spotted about 9pm on Hen Island after lighting a fire, and were taken to Marsden Cove.

Both men wore life jackets and told someone where they were going.

However, police say the pair didn't have adequate forms of communication.