Story highlights Authorities link suspect Salah Abdeslam to abandoned suicide belt, source says

A suspected gun dealer and his wife are held in connection with January attack

Separately, a 29-year-old man is detained in connection with last month's bloody attacks in Paris

(CNN) French authorities have established that at-large terror suspect Salah Abdeslam wore an explosive belt found on a Paris street 10 days after the November terror attacks, a source close to the investigation told CNN.

The source said that investigators had analyzed the suicide belt, found on a sidewalk on rue Frederic Chopin in the Paris suburb of Montrouge, and discovered traces of sweat that matched Abdeslam's DNA.

Investigators are working under the theory the Belgian-born French national was supposed to blow himself up in Paris' 18th arrondissement but backed out, the source told CNN.

In an ISIS statement claiming responsibility for the November shootings and bombings in the French capital, the terrorist group referred to an attack in the 18th district -- but none is known to have taken place there.

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The day after the suicide belt's discovery, Paris prosecutor Francois Molins said at a news conference an investigation was ongoing as to whether Abdeslam was planning a suicide attack in the 18th, and, if so, why it didn't happen.

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