Twenty-one houses were set on fire in Bihar's Nawada district on Wednesday evening, police said. Preliminary investigation suggested that a land dispute could be the cause behind the incident that happened in Manjhi Tola in Mufassil police station area, they said. No one was injured in the incident, they added. Ten people were detained, and a search was on to nab the other accused persons, police said. "A call was received around 7.30 pm that some houses were set on fire in Manjhi Tola. Police immediately reached the spot along with fire engines. It took some time to douse the blaze. According to villagers, a group of people started setting the houses on fire around 7 pm," said SP Abhinav Dhiman who also visited the area. "Preliminary investigation suggests that land dispute is the reason for the incident. A case has been registered and an investigation is underway," he said. Another police officer said shots were also fired in the air when the houses were being torched. Dhiman