TEHRAN, IRAN -- A top Iranian security official on Monday accused Israel of using "electronic devices" to remotely kill a scientist who founded the Islamic Republic's military nuclear program in the 2000s.

Ali Shamkhani, the secretary of the country's Supreme National Security Council, made the comment at the funeral for Mohsen Fakhrizadeh, where Iran's defence minister separately vowed to continue the man's work "with more speed and more power."

Israel, long suspected of killing Iranian nuclear scientists over the last decade, has repeatedly declined to comment on the attack.

Fakhrizadeh headed Iran's so-called AMAD program, which Israel and the West have alleged was a military operation looking at the feasibility of building a nuclear weapon. The International Atomic Energy Agency says that "structured program" ended in 2003. U.S. intelligence agencies concurred with that assessment in a 2007 report.

Israel insists Iran still maintains the ambition of developing nuclear weapons, pointing to Tehran's ballistic missile program and research into other technologies. Iran long has maintained that its nuclear program is for peaceful purposes.

Shamkhani's remarks drastically change the story of Fakhrizadeh's killing, which took place Friday. Authorities initially said a truck exploded and then gunmen opened fire on the scientist, killing him and a bodyguard. State TV even interviewed a man the night of the attack who described seeing gunmen open fire.

State TV's English-language broadcaster Press TV reported earlier Monday that a weapon recovered from the scene of the attack bore "the logo and specifications of the Israeli military industry." State TV's Arabic-language channel, Al-Alam, claimed the weapons used were "controlled by satellite," a claim also made Sunday by the semiofficial Fars news agency.

None of the outlets immediately offered evidence supporting their claims, which also give authorities a way to explain why no one was reportedly arrested at the scene.

"Unfortunately, the operation was a very complicated operation and was carried out by using electronic devices," Shamkhani told state TV. "No individual was present at the site."

Satellite control of weapons is nothing new. Armed, long-range drones, for instance, rely on satellite connections to be controlled by their remote pilots. Remote-controlled gun turrets also exist, but typically see their operator connected by a hard line to cut down on the delay in commands being relayed. Israel uses such hard-wired systems along the border with the Hamas-controlled Gaza Strip.

While technically feasible, it wasn't immediately clear if such a system had been used before, said Jeremy Binnie, the Mideast editor of Jane's Defence Weekly.

"Could you set up a weapon with a camera which then has a feed that uses an open satellite communications line back to the controller?" Binnie said. "I can't see why that's not possible."

It also raised the question whether the truck that exploded during the attack detonated afterward to try to destroy a satellite-controlled machine-gun that was hidden inside the vehicle. Iranian officials did not immediately acknowledge that. It also would require someone on the ground to set up the weapon.

Shamkhani blamed the Iranian exile group Mujahedeen-e-Khalq as well for "having a role in this," without elaborating. The MEK, as the exile group is known, has been suspected of assisting Israeli operations in Iran in the past. Shahin Gobadi, an MEK spokesman, dismissed Shamkhani's remarks as "rage, rancour and lies" sparked by the group's earlier exposes over Iran's nuclear program.

Monday's service for Fakhrizadeh took place at an outdoor portion of Iran's Defence Ministry in Tehran, with officials including Revolutionary Guard chief Gen. Hossein Salami, the Guard's Quds Force leader Gen. Esmail Ghaani, civilian nuclear program chief Ali Akbar Sahei and Intelligence Minister Mamoud Alavi. They sat apart from each other and wore masks due to the coronavirus pandemic as reciters melodically read parts of the Qur'an and religious texts.

Defence Minister Gen. Amir Hatami gave a speech after kissing Fakhrizadeh's casket and putting his forehead against it. He said Fakhrizadeh's killing would make Iranians "more united, more determined."

"For the continuation of your path, we will continue with more speed and more power," Hatami said in comments aired live by state television.

Hatami also criticized countries that hadn't condemned Fakhrizadeh's killing and warned: "This will catch up with you someday."

Overnight, the United Arab Emirates, which just reached a normalization deal with Israel, issued a statement condemning "the heinous assassination." The UAE, home to Abu Dhabi and Dubai, warned the killing "could further fuel conflict in the region."

Last year, the UAE found itself in the middle of an escalating series of incidents between Iran and the U.S. Though long suspicious of Iran's nuclear program, the Emirates has said it wants to de-escalate the crisis. The UAE just started passenger air service to Israel and Israelis are expected to vacation in the country over Hanukkah in the coming days.

Bahrain, an island kingdom off Saudi Arabia in the Persian Gulf that also recently normalized relations with Israel, similarly condemned Fakhrizadeh's killing.

"In light of the current situation in the region, the kingdom of Bahrain calls on all parties to exercise maximum restraint to avoid new levels of instability," Bahrain's Foreign Affairs Ministry said.

Meanwhile, Israeli Foreign Ministry Director-General Alon Ushpiz has sent a cable to all Israeli diplomatic delegations around the globe urging diplomats to maintain "the highest level of readiness and awareness of any irregular activity" around missions and Jewish community centres.

Hebrew-language media in Israel reported that following the Fakhrizadeh's killing, the Foreign Ministry ordered security increased at certain Israeli diplomatic missions overseas. The ministry declined to comment on diplomatic security matters.

------

Gambrell reported from Dubai, United Arab Emirates. Associated Press writer Ilan Ben Zion in Jerusalem contributed