CHIBA (Kyodo) -- Police arrested a 77-year-old man on Thursday in connection with the stabbing deaths of a couple earlier this week in Chiba Prefecture near Tokyo.

Kaoru Sakamaki, arrested for obstructing police duties, apparently had financial troubles with the couple, Toshiaki Watarai and his wife Reiko, who previously ran a real estate business, investigative sources said.

The couple, both 59, were found lying outside their home in Kashiwa on Wednesday evening, covered in blood with stab wounds to their upper bodies, and were later pronounced dead at a hospital.

The police have since opened a murder investigation.

They said a call was received from a neighbor around 6:10 p.m. reporting bodies being found at the property.

Just 10 minutes later, a fire was reported approximately 650 meters away, destroying eight houses and injuring two people. The fire is believed to have started at the arrested man's residence.