An elderly couple had a special delivery from UPS last week when five-pounds of marijuana was left on their front porch, according to Upper Darby Police.

The couple thought the package that arrived on their Heather Road doorstep was from Sears but once a package from Sears arrived on Thursday they opened up the original package and discovered the weed carefully packaged to avoid detection, cops said.

The couple turned the package -- it has a street value of about $23,000 -- over to police on Thursday.

The package was mailed from Arizona to the 100-block of Heather Road, however, the return address was a fake, cops said.

It wasn't clear whom the package was supposed to go to, police said.

"It could have been a trial run just to see if the law enforcement community was watching and could follow the package, said Police Superintendent Michael Chitwood. "Or... the receiver -- even though he or she does not live at that location -- they track the package (by) the computer so they know basically when the package is going to be delivered. And what they do is they intersect the driver of the particular delivery service."

As for figuring out who sent the package -- that will be left to the DEA to figure out.

"We see half a dozen of these types of deliveries a year and sometimes we're able to track down the sender," Chitwood told the Daily Times.

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