<?php
$m = new MongoClient();
$test = $m->selectDb('test');
$coll = $test->selectCollection('my_table');
$success = $coll->remove(array(
'_id' => new MongoId("54204806895f69383a8b4567")
));
dump($success);
^ array:4 [
"n" => 1
"connectionId" => 11
"err" => null
"ok" => 1.0
]