Source: Sharecast
M&S, which is currently not taking online orders as it grapples with the fallout from what it called a "cyber incident", is said to have ordered agency workers at the East Midlands logistics centre to stay home, according to Sky News.
Agency workers are thought to make up around 20% of the workforce at the Caste Donington site, which handles the retailer's clothing and homewares products.
Other employees at the centre, however, have been told to continue working as usual.
On Wednesday, M&S said it had moved some of its processes offline following a cyberattack "to protect our colleagues, partners, suppliers and our business".
The company had paused click-and-collect orders and stopped taking contactless payments, before suspending online orders completely on Friday.
On Monday, when trying to place an order on the M&S website, shoppers are faced with the following notice: "Products remain available to browse online and stores are open."
M&S shares were down 2.3% at 377p by 1213 GMT, having dropped around 8% over the past week.