Dutch officials have detected a second outbreak of bird flu on a southern Netherlands farm, officials said, and they are awaiting test results to see whether the strain was of a highly contagious variety discovered earlier this week.

The latest cases were detected in three barns containing 43,000 chickens on a farm at Ter Aar, just east of The Hague, the Dutch food and safety watchdog NVWA said Thursday.

The outbreak was of the H5 strain, but “it is not clear whether it was of the highly pathogenic variety or not,” added the Dutch economic affairs ministry in a letter sent to parliament on Thursday.

“The earliest results are expected by the end of tomorrow (Friday),” it said.

The powerful Dutch poultry industry has now been paralyzed for a second time this week with a nationwide ban on the transport of all poultry and related products that took effect starting at 2:00 p.m. on Thursday.

The ban will last up to 72 hours.

Authorities have also thrown a 10-km (6.2-mile) cordon around the farm, with four other farms also being tested for avian influenza.

The chickens are being destroyed and the farm disinfected, the NVWA added.

The European Commission said it was in “constant contact” with Dutch authorities and was ready to take further action once test results from the birds were through.

Dutch officials initially banned the transport of poultry around the Netherlands on Sunday after the discovery of a highly infectious strain of bird flu. Outbreaks of similar strains on the virus had previously occurred in Britain and Germany.

Some 150,000 birds were destroyed at the farm in Hekendorp, which lies about 25 km southeast of Ter Aar.

Officials have identified the flu as being the H5N8 strain, which had previously been detected only in Asia.

Some strains of avian influenza are fatal for chickens, and pose a health threat to humans, who can fall sick after handling infected poultry.

But Dutch authorities have said human infection can only occur following “intense and direct contact” with infected birds.