Search planes hunted on Monday for an aircraft carrying 16 people that is believed to have crashed in eastern Indonesia. Four planes were flying close to the route that the Twin Otter was taking before it lost contact with flight controllers on Sunday over the remote Papua region, said Air Force Col. Suwandi Mihardja. No trace of the small plane has been found, he said. The missing plane was on a 50-minute journey from Sentani, a major airport in Papua, to the town of Oksibil. Indonesia, a nation of more than 18,000 islands, has seen a string of air crashes in recent years. In 2007, the European Union banned all Indonesian carriers from landing in the bloc. It recently lifted the ban on four of the airlines, including Garuda, the country's flag carrier, saying standards had improved. Much of Papua is covered with impenetrable jungles and mountains. In the past, crashed planes there have never been found.