Weird behavior of mysqli->query for multiple DELETE

Question

I am running following query by using mysqli->query but despite of showing affected rows removing correct records,MYSQL is not removing the records. The same query runs perfect on command line.

DELETE m,s FROM t1 m
LEFT JOIN t2 s ON t1.sbid = t2.sb_message_id
WHERE m.sbuid = 11

mysqli->affected_rows gives correct count but its weird that records are not being removed.

OK just checked that even a single Delete query is not being executed. Let me also clear that I am deleting within a loop.