Fire crews have been working around the clock to extinguish last night's major blaze at a recycling centre on Auckland's North Shore

Heavy machinery is being brought in this morning to help extinguish hot spots, at the Abilities Group Recycling Centre in Wairau Valley.

The fire sent plumes of toxic black smoke across the city last night, but Fire and Emergency says the risk should now be contained to the local area.

Councillor Richard Hills says it's a major blow to the recycling charity, which provides jobs for people with disabilities.