MILAN, Feb 26 (Reuters) - Italian police have seized 46.8 million euros ($49.1 million) from a local unit of logistics giant Deutsche Post DHL DHLn.DE as part of the latest investigation into alleged tax fraud linked to illicit labour supply, prosecutors' documents showed.

In a 50-page decree reviewed by Reuters on Wednesday, Milan prosecutors accused DHL Express Italy srl of circumventing labour and tax laws through false invoices, relying on cooperatives or limited liability companies that supplied workers while omitting tax and social security payments.

The charges cover the period from 2019 to 2023.

Deutsche Post DHL confirmed that its Italian subsidiary was subject "to checks by the authorities".

"As this is part of an ongoing investigation, we cannot provide further details," a DHL spokesperson said, adding that the company is cooperating fully with the authorities and that its service to customers is not affected.

This is the second time that Milan prosecutors have issued such an order against a local unit of the German group, having seized more than 20 million euros from DHL Supply Chain in an investigation on the same charges in 2021.

The Italian authorities have targeted more than a dozen delivery and logistics groups over their labour practices in recent years. They have made seizure orders with a value of 634 million euros since 2021, including this latest move, documents from the prosecutors show.

In the latest decree, prosecutors said that DHL Express Italy, via intermediaries acting as filters, used "bogus procurement contracts for the provision of services" with these cooperatives or companies that were a front for cheap labour, and made false tax declarations.

They added that this business model "facilitates the exploitation of workers and results in unfair competition", and it has been common malpractice in Italy for years, if not decades.

Similar investigations into irregular hiring schemes, the last one in January into FedEx FDX.N, have targeted other large businesses including Amazon and GLS, U.S. logistic giant GXO Logistics GXO.N, German logistics firm DB Schenker and Italian supermarket chain Esselunga, Milan prosecutors said.

($1 = 0.9527 euros)

(Reporting by Emilio Parodi, additional reporting by Matthias Inverardi in Dusseldorf, editing by Keith Weir and Sharon Singleton)

((emilio.parodi@thomsonreuters.com; +39 06 8030 7744))