In the future, our quality of life will be determined by the quality of our cities.

Not everyone is a fan of self-driving cars.

Chandler, Arizona, is one of the Phoenix suburbs where Alphabet-owned Waymo is testing self-driving Chrysler Pacifica hybrid minivans, and where it debuted a commercial taxi-like driverless car service operated through an app earlier this month. Its driverless vehicles have weathered nearly two dozen attacks from irate locals over the past two years, including tire slashings and being pelted by rocks, according to the New York Times (paywall).

“There are other places they can test,” Erik O’Polka, 37, told the Times. O’Polka received a warning from police in November after reportedly making multiple attempts to run Waymo vehicles off the road using his Jeep Wrangler, including driving toward one of the Waymo cars head-on. O’Polka and his wife told the Times that they turned against Waymo after one of the company’s vehicles nearly hit their 10-year-old son while he was playing in a cul-de-sac.

“They said they need real-world examples, but I don’t want to be their real-world mistake,” O’Polka told the Times.

“They didn’t ask us if we wanted to be part of their beta test,” his wife, Elizabeth, added.

A lot has been written about what will happen to cities and their residents once driverless cars become ubiquitous. Generally speaking, it’s been taken as a given that people will want the technology. The vision is that self-driving cars will dramatically reduce auto fatalities while also reducing congestion and freeing spaces like parking lots for other uses as people give up their personal vehicles.

The incidents in Arizona, while relatively rare, suggest the transition won’t be so smooth. Many people are worried about what advances in automation like driverless cars could mean for their jobs. Others fear the technology will be deployed before it’s fully ready, increasing the dangers.

Arizona has particular reason to fear this. In March, one of Uber’s self-driving vehicles struck and killed a pedestrian at night in Tempe, another suburb of Phoenix. After the incident, Arizona’s governor banned Uber from testing autonomous cars and the company suspended tests throughout the US. Uber only recently resumed driverless car testing on US public roads.

The Arizona Republic, which first reported the assaults on Waymo, noted that people who monitor Waymo’s self-driving cars rarely press charges against harassers. One exception was 69-year-old Roy Leonard Haselton, who police arrested and charged with aggravated assault and disorderly conduct for aiming a handgun at a passing Waymo vehicle and its human driver.

The incidents have made Waymo employees wary of people or cars that seem to pay them too much attention. The Republic recently spent three days tailing dozens of Waymo minivans in the Phoenix metro area for more than 170 miles. After reporters watched Waymo’s operations for a while from a public sidewalk, a security guard approached to ask what they were doing, which prompted a call from Waymo’s press agency.

In another incident, a Waymo vehicle the reporters had tailed for half an hour pulled into a police substation, where two officers yelled for the reporters to stop. Police said Waymo had called out of fear their driver was being harassed. Based on the company’s history in the Phoenix area, it’s not surprising why Waymo thought that.