RIO DE JANEIRO, Brazil -- The couple followed their Waze GPS app, thinking it would lead them to a touristy avenue in Niteroi, a large city across the bay from Rio de Janeiro.

Instead, it led them to another street of the same name in Niteroi in one of the city's most notorious slum areas. The woman was shot and killed.

Regina Murmura, 70, a travel agent who had been using the Waze app while traveling through Niteroi with her 69-year-old husband, Francisco, was killed on Saturday night, according to a Brazilian police spokesman. The couple's app led them on a small road in one of the city's most notorious favelas, or slum areas.

Someone opened fire, with 20 bullets hitting the couple's car, the police spokesman said. Authorities don't know why, though drug gangs are prevalent in the area.

Francisco Murmura managed to drive away. He was not hospitalized.

Waze said it was "incredibly saddened" by the incident.

"Unfortunately it's hard to prevent drivers from navigating to a dangerous neighborhood if it's the destination they select," said the company, which was developed in Israel and is now owned by Google. "Citizens who reside in these areas need to be able to get home."

Concerns about GPS, security ahead of Olympics

The incident has raised concerns over security in and around favelas ahead of next year's Olympics in Rio and also over the use of GPS apps in a state where gang-controlled neighborhoods sit next door to tourist areas.

In the city of Rio alone, about 1.4 million people live in favelas -- or about a fifth of the population. In recent years, police have set up a permanent presence in dozens of the dangerous neighborhoods, but many are still controlled by drug gangs.

Waze said it would meet with officials at the Operations Center in Rio de Janeiro this week "to understand how the city is addressing the risk of driving throughout Rio de Janeiro."

In the case of Niteroi, a Brazilian actress made the same mistake two months ago, following her GPS into the Caramujo favela. She was shot at, but survived.

Police responded Monday to the latest incident in Niteroi by storming Caramujo, trading bullets with gang members, according to the police spokesman. No one was injured or arrested, but police said they have identified a suspect in Murmura's killing.