Extremely bright light lit up huge area behind hill, happened 5 times then somehting flew over us.Whitianga is a small tourist town next to a river, harbour and beach in the north island of New Zealand.I live in Auckland and drove to Whitianga to work on a yacht I had bought there. The yacht was moored at the furthest end of the river, I travelled there with two friends of mine; all of us are in our 40’s. We arrived at the boat ramp just before midnight; it was a very clear night, with no wind. As Whitianga is in the country, the stars there are very bright and we had often seen shooting stars. The countryside there is very hilly with a mountain range between us and Auckland on the opposite side of the river. Auckland, our biggest city is about 100km from Whitianga. I reversed the car down the boat ramp and proceeded to unload my inflatable and the rest of the gear with Barry. After about a minute I heard one of my friends, Peter yell out. He said, "What is that!" Barry and I turned around; Peter was looking at the other side of the river. We replied, "What?" Because we couldn’t see anything. Then, after about 2-3 seconds, a huge bright light, absolutely massive, lit up the entire sky for about 2 seconds then went of again, after 2-3 seconds it came on again. It did this 5 times, including the time that Peter saw it without us. The light was so bright, and covered such a vast area that I could only imagine that a nuclear explosion could cause something like that. After the fifth time, there was a pulsating light that covered a very wide area of the sky above us and was traveling over us, it was not very bright, but we could see it, and it also made a very low kind of growling noise like a dog snarling, but duller, it passed over us and was gone. I had seen UFO’s on two other occasions, but both Barry and Peter were skeptics, needless to say, they aren’t now.