Assertion 0 == g->n_members failed error (from libevent)

The full error message I get is "Error from libevent: bufferevent_ratelim.c:724: Assertion 0 == g->n_members failed in bufferevent_rate_limit_group_free".

This happened after the following sequence of events:

1. Tried to connect to google.com using tor to check my mail and got "Tried for 120 seconds to get a connection to [scrubbed]:993. Giving up. (waiting for circuit)" message appearing twice.
2. After a while I shutdown tor.
3. The above message appeared.

Please let me know if you need any more info.

Trac:
Username: mr-4