Update 12:15 p.m. According to RT, as well as Reuters the plane has still not been found. "The country's search and rescue agency is looking for the jet near one of many volcanoes that form the backbone of Indonesia's main island." reports Reuters. RT mentions that hijacking hasn't been ruled out. "They say [Indonesian Aviation authorities] that in case of a crash, an emergency beacon should have imminently gone off, which did not happen."
Update 11:02 a.m. Indonesia's Antara News has a bit more on the passengers. As RT initially reported, representatives from major airlines were on the plane for its demo flight, and now it seems, there were journalists on board too. "As far as I know the majority of passengers aboard the plane for a second joy flight in the afternoon are journalists," an Indonesian Air Force spokesperson said. "According to our record two journalists are from Angkasa magazine namely Doddy Aviantara and photographer Didik N Yusuf." They report that the plane is "still being traced".
Update 8:32 a.m. Bloomberg has more details about the plane's disappearance. "The plane disappeared from radar in West Java at around 2:33 p.m., after declining to 6,000 feet" reports the team at Bloomberg, citing a statement from Indonesia’s National Search & Rescue Agency.