A major airstrike has hit one of Iran’s most important and high-profile bridges, pushing tensions in the region even higher. On April 2, 2026, US and Israeli strikes targeted the B1 Bridge in Karaj, a city just west of Tehran in Alborz province.
The bridge, often called the Karaj B1 Bridge, was one of the country’s biggest infrastructure projects in recent years. It was either newly opened or just about to be fully operational when it was hit.
Iranian officials say at least 8 civilians were killed and 95 others were injured. The attack has also badly damaged a key road link that thousands rely on every day. Most importantly, it was the first major strike on a civilian infrastructure since the war broke out in February.
Trump claims responsibility, issues warning
A day after addressing the war situation from the Oval Office and offering no clear plan on ending the war, US President Donald Trump took responsibility for the strike in a social media post. He shared a video showing the bridge collapsing, with thick smoke rising into the sky.
Along with the footage, he warned Iran that there was “much more to follow” and urged Tehran to agree to a deal “before it is too late.” Iran has strongly condemned the strike, calling it an attack on civilian infrastructure.
Here’s everything to know about Karaj Bridge.
The tallest Iranian bridge, now cut in half
The B1 Bridge was not just another road project. It was seen as a major symbol of modern engineering in the region. Standing at about 136 meters, it was the tallest bridge in the Middle East. Its tallest pylon rose to about 136 meters, though some estimates say it reached closer to 156 meters above the ground.
Stretching roughly 1,050 meters in length, it was built across eight sections, with the longest span reaching about 176 meters. At nearly 38 meters wide, it had multiple lanes designed to handle heavy traffic moving through one of Iran’s busiest regions.
But after the strikes, the central section of the bridge collapsed. Reports say it was hit twice in quick succession.
US defends attack on Karaj bridge
From what US officials and defence analysts are saying, this bridge acted like a “critical artery”, basically a main route for moving ballistic missiles and drone parts. Over the past few weeks, US and Israeli strikes have already made it harder for Iran to launch attacks from its western regions. Because of that, Iran is believed to have shifted some of its launch systems deeper into central areas.
It was seen as one of the main routes connecting Tehran’s production and storage hubs to these active deployment zones in places like Alborz and beyond. By hitting it, the US wanted to break the supply chain before the weapons even got into position.
A lifeline between Tehran and Karaj
The bridge sat on the Karaj Northern Bypass, a key route just west of Tehran in Alborz province. This road connects the capital to Karaj, Iran’s fourth-largest city, and further on to the northern provinces and the Caspian Sea region.
Cutting down hours of traffic
Anyone familiar with the Tehran-Karaj route knows how bad the traffic can get. With dense population and heavy industrial activity, congestion has long been a problem. The B1 Bridge was designed to fix that. In many cases, it could cut travel time by more than an hour. For daily commuters. It also meant lower fuel use and smoother movement across the region.
Boasting trade and daily business
The bridge played a big role in the economy, too. It helped move goods between cities, factories, and northern trade routes. Trucks carrying supplies and products depended on this route to keep things moving. For a country working under economic pressure, improving internal logistics like this was seen as essential.
A costly but important investment
Building the bridge didn’t come cheap. The project was valued at around $400 million, making it one of the bigger infrastructure investments in the region. For Iran, it was part of a bigger push to strengthen its transport network and rely less on outside help.
It was new and reportedly under construction
By early 2026, the bridge was either newly opened or in its final stages before full inauguration.
Its tall structure, cables, and wide deck had already made it a familiar sight in local media. In some of the last images before the attack, cranes could still be seen nearby, suggesting finishing touches were still underway.
The strikes that brought it down
On April 2, 2026, the bridge was hit in two rounds of airstrikes about an hour apart. The central section took the direct hit. The second strike came when responders were arriving at the scene.
The middle of the bridge collapsed, leaving huge gaps in the structure. Steel twisted, concrete broke apart, and sections of the deck fell away. It now stands split in half.
Civilians caught in the attack
Iranian officials say 8 civilians were killed and 95 others injured. Among those who died were people who had rushed in after the first strike to help. Many of the victims were workers or bystanders near the site.
A strike that will escalate the conflict
The US claimed responsibility for the attack. Trump also asked Iran to reach a deal “before it is too late.” Reports suggest the strike may have been aimed at disrupting supply routes, possibly linked to missile or drone movement. But the impact has gone far beyond strategy.
The destruction of the bridge has disrupted daily life, slowed trade, and raised fresh fears about how vulnerable such large civilian projects can be during conflict.
Iran has vowed retaliation, and tensions continue to rise. For now, rescue teams are still working at the site, and the future of the bridge remains uncertain.