People are being urged not to interfere or touch any of the containers and debris found washing up from the Rena wreck.

Containers and debris are washing up on Waihi Beach this morning, and more oil is expected on beaches from Mount Maunganui to Papamoa today after the ship broke in two during the weekend.

Waihi Beach is proving popular with sightseers heading there to look at washed up containers and their spilled milk powder debris.

Maritime New Zealand is asking people who come across any containers not to attempt to open them, but to contact the container and wildlife response line on 0800 333 771.

Up to 300 containers have been lost overboard, with most expected to have sunk.

Debris including milk powder and polystyrene are washing up in areas northwest of Tauranga.

Maritime New Zealand spokesperson Bruce Fraser says anyone who comes across containers should not try to open them as some contain hazardous materials.

'There are some with materials that should not be touched – they should report them and leave them alone.”

Anyone who discovers a container is urged to write down the container ID number and details of debris and location, and send any photos of the affected area and report to the container hotline.

There are at least five containers washed up on Waihi Beach.

The Bay of Plenty Regional Council has also established a ‘cautionary area' around the Rena following its release of containers and debris.

This includes the area from Waihi Beach to Mayor Island and includes Maketu.

All vessels should proceed at slow speed, keep a good lookout and travel through the area in daylight only.

The debris field is extensive and its movement is unpredictable and could extend further.

Bay of Plenty District Health Board is warning people swimming in the ocean to be careful of any debris or oil in the water.

Anyone who comes into contact with oil while swimming or on the beach should leave the area and clean it off using soap and water.

If people get oil in their eyes they should flush it out with clean, fresh water for 15 minutes.

If anyone has concerns about being exposed to oil, or have persistent symptoms such as skin irritation or a cough they should phone the Healthline for advice on 0800 611 116.

Anyone who smells or sees oil in the water should report it to surf life savers or contact the 0800 OIL SPILL response line.

A three nautical mile exclusion zone remains in place around the ship, still grounded on Astrolabe Reef, about 25 kilometres from Tauranga.

Anyone found in the exclusion zone without the express permission of the harbourmaster may be or fined $200 or could be prosecuted.

Contact Numbers

Oiled wildlife, container and debris sightings: 0800 333 771

Pxt and email photos or reports of containers to rena@braemarhowells.com or 027 897 4259

Oil spill sightings: 0800 645 774

Public health queries: 0800 611 116

Iwi liaison 0800 AWHI ME / 0800 294 463