A sharp rise in US pedestrian deaths has been partly blamed on people using their smartphones while driving or crossing the road.
The US Governors Highway Safety Association estimates that there were 6,000 pedestrian deaths in 2016, the highest number in more than 20 years.
In the last six years, fatalities have grown at four times the rate of overall traffic deaths.
The report says a number of factors are to blame, including mobile use.
"A more recent factor contributing to the increase in pedestrian fatalities may be the growing use of smartphones by all road users, which can be a significant source of distraction for both drivers and pedestrians," the report stated.
Other factors include increased driving, due to an improved economy, lower petrol prices and more walking for exercise and environmental reasons.
Alcohol is also blamed, with 34% of pedestrians and 15% of drivers involved in fatal crashes being intoxicated at the time.
The report is based on data from all states for the first six months of 2016.
The UK's Royal Society for the Prevention of Accidents said it also saw mobile phones as dangerously distracting.
"More and more older teenagers and young adults are being injured as a result of 'distraction', as a result of crossing [roads] while using their phone. This can be as a result of having a conversation, listening to music, texting or using the net," said road safety manager Nick Lloyd.
Some cities around the world are taking measures to counter the issue of smartphone distraction.
In the Bavarian town of Augsburg, the station has fitted red and green lights in the ground to warn people who "stubbornly look at their smartphone".
Officials in the Dutch town of Bodegraven ran trials in February of traffic lights that project a red or green lighting strip across the pavements to alert smartphone "zombies" who were glued to their mobiles as they cross the road.
"Social media, games, WhatsApp and music are major distractions in traffic," town alderman Kees Oskam said at the time.
Dutch road safety group VVN said that the idea "rewarded bad behaviour".