A popular brand of instant noodles that was supposed to be back on store shelves Monday following a food safety scandal actually resumed sales a day earlier at some stores, surprising hard-core fans.

Maruka Foods Corp. was to resume sales of its Peyoung brand instant noodles in the Kanto region beginning Monday, the company had said earlier. Some stores in Tokyo jumped the gun at around noon Sunday.

Many people tweeted they unexpectedly found their favorite noodles a day earlier and bought dozens of packages.

On Monday morning, stores across Kanto had the noodles on their shelves, attracting a number of customers who had been waiting months for the sales resumption.

At Beisia Maebashi Minami Mall supermarket in Gunma Prefecture, sales of the noodles were limited to three packs per customer.

"I bought one at a convenience store before coming here. It's a shame because I was going to buy boxes here," said Yusuke Shimoda, who was shopping at the Beisia mall.

Maruka Foods aims to resume nationwide sales early next month.

Sales of the product were suspended in December after a customer complained that an insect was found in the noodles.

The company resumed production at one of its two plants in Gunma Prefecture and redesigned the package.

The firm said it has implemented measures to block insects from entering the factory, such as filling up all openings where insects can go through. It added that it installed cameras to monitor the noodles before they are packaged.