SAN FRANCISCO (CBS SF) –The theft of a squirrel monkey from the San Francisco Zoo has many questioning security at the facility.

Although Banana Sam was found nearby at Stern Grove on Saturday and returned safely to the zoo, officials have increased the number of overnight officers on site and added surveillance cameras after the disappearance was reported.

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Robert Icard, Vice President of Operations at the San Francisco Zoo, said that because the thieves likely broke in after 11 p.m. on Thursday night, he has increased security guards working the graveyard shift.

“There are two additional officers patrolling the main campus as well, concentrating especially on the squirrel monkey (area) and some of the farther reaches of the zoo,” said Icard.

KCBS’ Anna Duckworth Reports:

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He said that there were no surveillance cameras in the back of the zoo, which is where culprits cut through the chain that locked an eight foot tall fence topped with three rows of barbed wire to get in.

So surveillance cameras have since been put up there and one other area around the zoo’s perimeter.

“Just because of the location of it and where the trees are, it’s very dark, even with the lights that are there,” said Icard. “So we just relocated some of our cameras to those locations.”

The overnight patrols will now include walking the external perimeter of the zoo’s fence as well as the internal side. Icard said that having two sets of eyes on either side of the fence can only help.

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