A suspect is arrested for not returning the cash that fell out of an armor in Hong Kong on Dec 25, 2014. [Photo/Ming pao]

Two people were arrested in Hong Kong on Thursday on suspicion of theft for not returning the cash that fell out of an armor van on Christmas Eve.

A taxi driver who saw a man and his girlfriend grab the money and who drove them home on Christmas Eve tipped off police, the Ming Pao newspaper reported.

Police recovered HK$161,500 ($20,000) from the home of the suspect and would continue to search the apartment of the female suspect, the paper said.

HK$15.23 million was found missing on Wednesday after three containers of cash spilled on the Gloucester Road in Hong Kong from a cash carrier.

TV footage shows drivers and pedestrians scrambling to scoop up the money scattered all over the road before armed police officers rushed to seal off the area.

Authorities said 29 people have already returned HK$5.69 million after police issued a warning that they could face up to 10 years in jail for theft.

The four guards escorting the armor were suspended Thursday and police said initial investigation showed they did not take part in the loot.

The rear door of the vehicle was reportedly not properly closed but a security expert told the Ming Pao that the doors of cash carriers are protected with more than one procedure and are specially guarded and it is extremely rare for cash boxes to fall out.