A cyberattack on Askul is disrupting e-commerce and logistics for major Japanese retailers including Muji owner Ryohin Keikaku.

It’s the second such incident to unsettle the country’s consumer market in less than a month. Household goods seller The Loft and Sogo & Seibu retail chain have also suspended their e-commerce sites.

Ryohin Keikaku, which didn’t offer a timeline for the resumption of online sales, said its own system hasn’t been compromised and store logistics and deliveries are unaffected by the incident.

The Loft, owned by York Holdings that recently spun off from Seven & I Holdings, also said in a Monday statement that the resumption of its e-commerce operations has yet to be determined.

Sogo & Seibu said it halted orders and shipments of some products due to the attack and has yet to determine when its services will resume, according to a statement.

The disruptions stem from a Sunday ransomware attack that crippled the system of Askul, a Japanese seller of office supplies, forcing a suspension of orders and shipments.

The incident comes just weeks after Japan’s largest brewer, Asahi Group Holdings, suffered a cyberattack that disrupted production and shipments of its “Super Dry” beer, Japan’s most popular brew. It caused the company to postpone the reporting of third-quarter financial results.

The latest disruption will raise questions about the vulnerability of Japan’s e-commerce infrastructure, especially with many retailers sharing the same online vendors.

Askul is investigating whether client or personal data were compromised, it said on Monday. The company is assessing the financial impact of the attack and may postpone the release of monthly earnings data scheduled for Oct. 28, it said.

Ryohin Keikaku’s e-commerce exposure is low and the site suspension will have limited impact on the company, said Daisuke Aiba, a retail analyst at Iwai Cosmo Securities.

But Askul is likely to see “significant” impact to its earnings as recovery from such attacks typically takes time and may put off customers especially if the disruption is prolonged, he added.