Adding a bit of info collected mostly on reddit:

bitcoin24 currently has two problems:

- bank accounts being frozen due to investigation of potential money laundering
Apparently they had problems with the german account from the start, due to allowing large deposits and withdrawals and having no verification system in place. So people used phished access to other peoples accounts to deposit large sums and used bitcoins to launder.
At the very start of bitcoin there was supposedly an investigation but dropped.
Its back now and both the german account as well as the polish (which he has as "workaround" of the problems in germany at first) are getting frozen.

- trading engine bug that gave a number of users double, triple, ... the BTC they should get. Transactions will have to be rolled back and the bug fixed before any BTC can be withdrawn.
If he will actually be able to allow that once its fixed isnt clear due to problem 1