killThread -package:thread-hierarchy

killThread raises the ThreadKilled exception in the given thread (GHC only).
killThread tid = throwTo tid ThreadKilled
Lifted version of killThread.
Generalized version of killThread.
Raise the ThreadKilled exception in the target thread. Note that if the thread is prepared to catch this exception, it won't actually kill it.
Registering a timeout action of killing this thread. TimeoutThread is thrown to the thread which called this function on timeout. Catch TimeoutThread if you don't want to leak the asynchronous exception to GHC RTS.
Registering a timeout action of killing this thread and unregister its handle when the body action is killed or finished.