Someone gained access to this account

and started a Powerdown, I have since changed my password however
not before he stole 100.587 Steem and 17.243 SBD from my account.

It is still unclear how they gained access to the key, it makes
me wonder if the Steem-Engine has been compromised.

How do we flag this thief? Hive account@andrarchy Hive account@steemitblog Hive account@ned Hive account@steemcleaners

I am starting here http://steemcleaners.com/reports/new

The STEEM and SBD in question is still there in this account, along with other users funds.
https://steemitwallet.com/@newcastle/transfers

The first unauthorized transaction is https://steemd.com/tx/cda9aeadc93774f0a4c2987f76f9bca4107e3164
The second was https://steemd.com/tx/6013a511ec05b643400d7063d1c38eead692b5c9

Then they set a new vesting route to newcastle https://steemd.com/tx/b80a2a221c525082347aa3651894338bba57d0e2
And withdrew another 34.082 SP, followed by this

designpod withdraw 0.000 SP as 0 STEEM (show details) 5 days ago
virtualdesignpod withdraw 2.622 SP as 2.620 STEEM to newcastle (show details) 5 days ago
virtualdesignpod withdraw 0.000 SP as 0 STEEM (show details) 12 days ago
virtualdesignpod withdraw 2.622 SP as 2.619 STEEM to newcastle (show details) 12 days ago

So another 5.239 STEEM, so in total I am missing 139.908‬ STEEM and 17.243 SBD.

Please advise.