In Short: A flight that got off from Surabaya to Singapore has disappeared midflight. The officer requested an unusual route due to the monsoons and disappeared soon after that.
There is also a report about a plane crash near the Belitung (translated)
Source: http://nasional.kompas.com/read/2014/12/28/10400961/Ada.Pesawat.yang.Jatuh.di.Perairan.Belitung.Timur
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I hope they are alright but to be honest, it doesn't look to great. A short distance between two destinations, monsoons and a 4 hour landing overdue makes it very likely that it has already crashed.
There is also this (not sure if its official)
(http://i-cdn.embed.ly/1/display?key=fd92ebbc52fc43fb98f69e50e7893c13&url=https%3A%2F%2Fpbs.twimg.com%2Fmedia%2FB57A2OUCMAAqxdR.png%3Alarge)