Lae's lockdown comes as Covid-19 infections spike Lae, Huon Gulf and Nawaeb Districts.
The latest figures from the Royal Papua New Guinea Constabulary put the current infection rate at 1741, with 49 new cases reported this Tuesday. The death toll remains at 16.
The Morobe Provincial Emergency Operations Committee issued an edict saying a 'no-mask, no-entry" rule would apply to all government offices and businesses. This also applies to Bougainville Island.
Bars, social clubs and gambling houses are closed until 19 March while totels, motels and guest houses must comply with the various directives.
Shops and traditional markets can open but customers must wear masks, wash hands and sanitise before entering.
Sports events and large gathering cannot go ahead, but church services can, if congregation size is limited to 50 people.
The committee directive said a failure to comply would result in penalties under the National Pandemic Act.
Meanwhile Port Moresby's main hospital is being forced to restrict its services as the capital is also confronted by more Covid-19 cases.
Covid-19 infections have soared. In the past five weeks hundreds of new cases have been reported in the country with Port Moresby the worst hit.
Port Moresby General Hospital chief Dr Paki Molumi said they was having to prioritise services.
The Consultation Clinic is being shut for two weeks, with staff moved to other areas.
Only emergency surgery is being undertaken, while all elective surgery is on hold until further notice.
The Emergency Department will be open but the public is being encouraged to use other medical clinics.
There will be no Gynaecology Clinic, while the Antenatal Clinic will continue but with limits on bookings.
There will also be limited imaging services available, however blood services will remain at the Pathology Department.
On Bougainville Island, the government issued an advisory saying public services were being scaled down.
People were being encouraged to use devices to contact offices to limit face to face interaction, while they were also encouraged to make no more than one trip outside of Bougainville each month.
The government called on all departments to support the food donation initiative from the Bougainville Department of Health to feed households where there were confirmed Covid-19 cases.