Circuit_breaking_exception [parent] Data too large

Got this dreadful circuit_breaking_exception

The cause is known : I accidentally started creating one index per event. Bad idea !

I stopped the offending logstash instance, so my cluster is not under load anymore. Unfortunately, it is in such a state that I can't even delete the badly created indices.

How could I get back my elastic cluster in a working state ? Should I perform a full cluster restart ? I suspect that even doing so, elastic will try to process its queue and remain stuck.

Any way to restart an elastic cluster without processing the pending operations ?

What is the output from _cat/health?v?
What is the output from the _cluster/stats?pretty&human API?