A man who was "driving dangerously at excessive speeds" has crashed four times across east and south Auckland, injuring a motorcyclist.

Senior Sergeant Graeme Fleming said Counties Manukau Police were appealing for witnesses to a number of serious driving incidents across the district this morning.

The alleged driver is now in custody.

After 8.40am police received reports about a man behaving erratically in the Mt Richmond area following a reported family harm incident.

Shortly later police began receiving reports about a blue Holden Commodore being driven dangerously in the Otahuhu area on Great South Road.

"Police believe the vehicle has continued to drive dangerously through Papatoetoe and Otara," Fleming said.

"The vehicle has later been involved in a crash with a motorcycle at the intersection of Te Irirangi Drive and Dawson Road, Clover Park."

The motorcyclist suffered moderate injuries, Fleming said.

The driver continued down Dawson Rd before colliding with another vehicle.

At this point, the driver has fled from the Commodore and stolen a vehicle to flee in.

The driver has crashed again in the Murphys Rd area and proceeded to steal another vehicle.

"He has continued to drive dangerously toward the Howick area before being involved in another crash at the intersection of Bleakhouse Road and Ridge Road about 10am," Fleming said.

He has attempted to steal another vehicle at this time.

Police staff had been actively looking for this person.

The alleged driver was found and taken into custody by police in Howick thanks to information from members of the public.

"The man was driving dangerously at excessive speeds that caused serious risk to the public and it is incredibly fortunate that nobody was seriously injured," Fleming said.

Police would like anyone who witnessed the man's driving or were involved in any of the incidents to contact police on (09) 261 1321.