Extinction Rebellion protesters block A38 in Birmingham
Climate change campaigners blocked one of the busiest roads in and out of Birmingham during rush hour.
Up to 40 protesters from Extinction Rebellion stopped traffic for seven minutes at a time on the A38 Bristol Street between 08:00 and 09:00 BST.
Disrupted motorists included a pregnant woman who was being driven by her partner to hospital to give birth.
West Midlands Police officers were in attendance. The force said no-one had been arrested.
Up to 1,000 members of Extinction Rebellion staged an 11-day protest in April, which brought several parts of London to a standstill.
The group, which wants to cut greenhouse gas emissions to net zero by 2025, has also used boats to stop traffic in Cardiff, Glasgow, Bristol and Leeds.
The protest on Wednesday morning sparked angry responses from some drivers who honked their horns and shouted they "needed to get to work".
Police confirmed one of the passengers trying to get through was pregnant and on her way to hospital.
Protester Eve Jones, 50, a teacher from Birmingham, apologised for the disruption.
"It's not in any way an attempt to target, inconvenience or blame ordinary people," she said.
"What we are here to do is force the government to pay attention to the issue of climate change and take urgent and decisive action."
She added: "I have two children and I'm scared for their future."
Retired plumber Bruford Low, 57, from Lichfield, said the group was "only too aware that this sort of action causes anger and upset".
"But I feel angry and upset about the climate situation," he said.
"I've never protested before in my life, but I've looked at the science behind this problem and we have a very limited amount of time.
"If we don't take action within the next 18 months it may well be too late."
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Another protester, Jeanne Bouvier, a health care assistant from Edgbaston, said it was important to take part in the protests.
"We want the government to act and reduce gas emissions to net zero by 2025," she added.
One of the motorists caught up in the disruption, 55-year-old Stuart Fereday from Kings Norton, said he had not heard of the group before but the protest had made him "sit up and take note".
Before the protest began, police said they would be "present in the area to ensure public safety is maintained".
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