Seven baby monkeys died from poisoning at US research center

• Young primates died after contact with toxic dye
• 'Invasive and deadly experiments " must end' say campaigners

Seven infant monkeys were accidentally poisoned and died at one of the largest primate research centers in the US, internal documents shared with the Guardian have revealed.

The young macaques died after their mothers were marked with dye at the University of California, Davis, primate research laboratory.