HONG KONG — An electronics manufacturer in Taiwan said Wednesday that a company based in Hungary made the pagers bearing its brand that were used by members of the militant group Hezbollah and exploded simultaneously across Lebanon on Tuesday.

At least 12 people were killed and more than 2,750 others were injured in the blasts, according to the Lebanese Health Ministry. In a statement Wednesday, the Iran-backed Hezbollah said there would be a “severe reckoning” over the blasts, blaming Israel.

Israel has not commented directly on the explosions, but two U.S. officials and a senior diplomat in the Middle East told NBC News that Israel was behind the attack.

Images circulating online show destroyed pagers in Lebanon whose features are consistent with those made by Taiwan-based Gold Apollo. The company’s founder and president, Hsu Ching-kuang, told reporters Wednesday that the pagers were made by another company licensed to use its brand.

“There is an agent in Europe whom we have cooperated with for three years, they are the agent for all of our products,” Hsu said at the company’s offices in the northern Taiwanese city of New Taipei.“We are not a big company, but we are a responsible company that cares about our products,” he said.

In a statement, Gold Apollo identified the other company as the Hungary-based BAC Consulting. The company is authorized to use Gold Apollo’s logo for product sales in certain regions, “but the design and manufacturing of the products are entirely handled by BAC,” the statement said.

Reached by phone Wednesday, BAC Consulting Chief Executive Cristiana Bársony-Arcidiacono confirmed that her company worked with Gold Apollo. But when asked about the pagers and the explosions, she said, “I don’t make the pagers. I am just the intermediate. I think you got it wrong.”

Records on the Hungarian Ministry of Justice show that a firm with the name BAC Consulting was registered as a new company on May 21, 2022. Its main activities listed retail trade of telecommunications products, as well as management consulting, jewellery making and cultivation of fruit.

A record from May 2, 2020 suggests that a company of the same name had existed in the past and was shut down in 2020.

Zoltan Kovacs, a spokesperson for the Hungarian prime minister said on X that authorities have confirmed that BAC Consulting was a trading intermediary that was not manufacturing or operating in Hungary, and that “the referenced devices have never been in Hungary.”

He emphasized that, “this case poses no national security risk” to the country.

A spokesperson for Gold Apollo declined to comment further Wednesday, citing the ongoing investigation.

Taiwan’s Economic Affairs Ministry said Wednesday that Gold Apollo had exported 260,000 pagers from 2022 to August 2024, primarily to European and American markets. In a statement, it said there had been no reports of explosions related to those products and that there were no records of the company exporting pagers directly to Lebanon.“Was this batch of goods actually modified? … Did another manufacturer produce them and simply label them with the Apollo brand? This part is still under investigation by the authorities,” a ministry spokesperson told NBC News.

The explosions Tuesday come amid rising concern that tensions between Israel and Lebanon could spiral into all-out war. Israel and Hezbollah, which is based in Lebanon and opposes Israel’s military assault on the Gaza Strip, have been engaged in cross-border attacks since the start of the Israel-Hamas war last October, displacing thousands of people in both countries.

The Lebanese Foreign Ministry condemned what it called an “Israeli cyber attack,” saying that it would lodge a complaint with the United Nations Security Council.

Jeanine Hennis-Plasschaert, the U.N. special coordinator for Lebanon, said Tuesday that the explosions marked “an extremely concerning escalation in what is an already unacceptably volatile context.”

State Department spokesperson Matthew Miller said Tuesday that the U.S. was “not aware of this incident in advance” and not involved in it.

However, two U.S. officials told NBC News that Israel was behind the attack, while a senior diplomat in the Middle East commented “this is undoubtedly an Israeli operation” when asked about the pager attack. The United States and other Western governments are still gathering information about the attack and how it was carried out, two U.S. officials and a Western official said.

It was unclear why Israel carried out the attack when it did and whether it was an opportunistic operation or something more strategic that would be followed by other actions, the officials said.

The officials did not confirm reports about how the devices were possibly tampered with and designed to detonate.

Videos suggest that explosive devices were integrated into the pagers, said N.R. Jenzen-Jones, director of Armament Research Services, a technical intelligence consulting firm.“The scale suggests a complex supply-chain attack, rather than a scenario in which devices were intercepted and modified in transit,” he said on X.

Pagers are favored by members of Hezbollah who avoid using cellphones for fear that Israel could use them to track and monitor them. Lebanese officials warned the public Tuesday to stay away from their wireless communication devices pending further notice.

Hezbollah said it was investigating the explosions and that there would be a “severe reckoning that the criminal enemy must face for the massacre it committed on Tuesday against our people, our families and our fighters in Lebanon.”

The group said earlier that “a girl and two brothers” were among those killed by the explosions, some of which appeared to have been captured on closed-circuit TV video and shared on social media. Muhammad Mahdi, the son of Ali Ammar, a Hezbollah member of Parliament, was also reportedly killed.

Hsu of Gold Apollo said he also felt he had been victimized and was considering filing a lawsuit.

“I am a businessman,” he said. “How did I get involved in this attack?”