Nine men have been arrested on suspicion of child sex crimes after an 'exploitation investigation' in Derby, England, wrote dailymail.co.uk.

The men were held on suspicion of what police have described as 'conspiracy of sexual activity with a child' and remained in custody on Saturday morning.

Officers carried out warrants in Loudon Street and Walbrook Road in Normanton and Pear Tree about 10pm on Friday and arrested six men.

Another three were arrested in the early hours of Saturday morning.

The nine men were aged between 20 and 47 with eight from Derby and one from overseas.

Neighbours said men had been 'seen coming and going' one of the houses before it was raided.

One woman, who lives in Loudon Street, said there was a lot of noise after new tenants moved into the rented house a month ago.  

'There's been loud music. There always seems to be different people about. I saw loads of men coming and going at all times,' she told the Daily Telegraph.

'It was about 11pm when I was aware the police were here. There were quite a few of them and it was clear something serious was happening.

'I'm a mother to two children so it's really shocked me. But I feel reassured that the police are here. That does make me feel better.'

Normanton resident Simon Bacon said he witnessed a man being taken away by police in handcuffs in Walbrook Road last night.

'I was driving past when I saw an adult man being taken away by a policewoman in handcuffs,' he said.

'It's not unusual to see police in Walbrook Road but news of this type of investigation is very shocking. I'm really pleased to see the police taking action. That's very positive and shows they act on intelligence.' 

Derbyshire police said the investigation was still in its early stages and any updates would be released at the earliest opportunity.

Superintendent Tracy Harrison said the force would increase the number of officers on patrol in the area over the coming days. 

'Our officers will be out in the community to offer reassurance to people living in the area,' she said.

'I would encourage anyone who has any concerns or wants to talk about issues in their neighbourhood to go up and have a chat with the officers.'