Updated: Thu, 08 Aug 2013 18:36:42 GMT | By Alexandra Pournaras and Tracy Connor, NBC News

Whitey Bulger jury examining submachine gun

James 'Whitey' Bulger in an undated photo entered into evidence by his lawyers.

James 'Whitey' Bulger in an undated photo entered into evidence by his lawyers.

Jurors in the Whitey Bulger trial asked Thursday to examine a submachine gun with an obliterated serial number that is linked to the last count of the federal indictment.

The German-made MP 40 — known as exhibit 933 — was sent back to the room where jurors were in their third day of deliberations. It was unclear why the panel wanted a closer look.

Bulger, 83, is accused of 19 murders and raft of other crimes, including firearms violations, as leader of South Boston's fearsome Winter Hill Gang.

The eight men and four women on the panel have asked the judge several questions, including whether there is a statute of limitations on any of the charges, which cover crimes dating back to the 1970s. No statute of limitations applies in the case.

Jurors also wanted to know if they needed to be unanimous to find that prosecutors had not proven one or more of 33 criminal acts that are outlined in a count of racketeering.

They only need to find that the government proved Bulger committed two of the acts to convict him of racketeering, but the judge instructed them to try and reach agreement on all of the acts if they can.

Bulger, 83, who spent 16 years on the lam before being captured in California, faces life in prison if he's convicted of murder or other top charges. If he's acquitted, he could still face charges in state courts.

His trial has seen a rogue's gallery of admitted killers take the stand to describe how he allegedly choked the life out of two women with his bare hands and killed or ordered hits on a slew of rivals and suspected rats.

Bulger has cursed out witnesses who described him as an FBI informant and told the judge last week that the trial was a sham.

"As far as I'm concerned, I didn't get a fair trial," he said, announcing that he had decided not to testify in his own defense. "Do what you want with me."

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