In less than nine months, an assassin on a motorbike fatally shot an Al Qaeda commander given refuge in Tehran, Iran’s chief nuclear scientist was machine-gunned on a country road, and two separate, mysterious explosions rocked a key Iranian nuclear facility in the desert, striking the heart of the country’s efforts to enrich uranium.

The steady drumbeat of attacks, which intelligence officials said were carried out by Israel, highlighted the seeming ease with which Israeli intelligence was able to reach deep inside Iran’s borders and repeatedly strike its most heavily guarded targets, often with the help of turncoat Iranians.

The attacks, the latest wave in more than two decades of sabotage and assassinations, have exposed embarrassing security lapses and left Iran’s leaders looking over their shoulders as they pursue negotiations with the Biden administration aimed at restoring the 2015 nuclear agreement.

The recriminations have been caustic.

The head of Parliament’s strategic center said Iran had turned into a “haven for spies.” The former commander of the Islamic Revolutionary Guards Corps called for an overhaul of the country’s security and intelligence apparatus. Lawmakers have demanded the resignation of top security and intelligence officials.

Most alarming for Iran, Iranian officials and analysts said, was that the attacks revealed that Israel had an effective network of collaborators inside Iran and that Iran’s intelligence services had failed to find the moles.