Matson Navigation Co. has reached a tentative agreement with three unions that averts a widespread shipping strike, according to Jeff Hull, a Matson spokesman.

Earlier today, the American Radio Association, which represents radio officers on Matson container ships, went on strike in Seattle today at 5 a.m. Hawaii time.

Other unions, including the International Longshore Warehouse Union, honored the picket line and stopped loading the MV Maui , Hull said.

“The pickers in Seattle will be called away and will start” working on the HV Maui, Hull said this afternoon. The agreement is subject to ratification by all three unions.

Negotiations  with the ARA and two other unions representing ship captains and officers and engineers continued into this afternoon in California.

The strike this morning was only in Seattle and operations at other ports were not affected.

The MV Mahimahi left Los   Angeles today for Honolulu and perations at Honolulu Harbor  also continued with the arrival of the MV Manoa and the scheduled departure of the MV Mokihana.

The ARA, Masters Mates & Pilots, and the Marine Engineers Beneficial Association represent about 1,000 to 1,500 members eligible to work for Matson. Their contract expired June 15.