Investigations are under way after it was revealed that the number of pedestrians injured on the city's roads has risen by more than a third in the last 12 months.

There has been a rise of 25 casualties, including an increase of three killed or seriously injured, in the past year, with the overall number of people injured on the city's roads also rising.

As a result, council officials have revealed that investigations have started to find the cause of this increase.

The overall number of casualties on roads in Norwich has gone up by 30 people in the last year, with those killed or seriously injured increasing by four in the past year and nine over two years.

In the last 12 months there have been 419 casualties, with 389 from July 2009 to June 2010, and 380 from July 2008 to June 2009.

A large proportion of the overall increase was through injuries to pedestrians, with 94 casualties in the past year, including 16 who were killed or seriously injured. This overall figure was a rise of just over 36pc in a year, with 25 more casualties, including an increase in three killed or seriously injured.

The number of injuries to children has stayed the same.

The latest figures have been provided to the Norwich Highways Agency Committee and a report said the figures for Norwich went against a trend elsewhere in Norfolk, which has seen a decrease over the past two years.

However, it added that the long term progress has been good and that the numbers of casualties remain below targets.

Since 1996, Norfolk county county and Norwich city council has worked together to manage the committee.

John Birchall, spokesman for the county council, said: 'The number of people killed or seriously injured on the roads in Norwich has been on a downward trend for the last 15 years, but the latest figures for the city suggest that this may be changing.

'We are anxious to find out whether there are reasons for this, particularly among pedestrians. That work is under way, and we are gathering information on all these accidents to see whether there are common features.

'We will then be able to see whether there any steps that can be taken to improve safety. It is too early to come to any conclusions.'

Amy Lyall, city council spokesman, said: 'We take any rise in these figures very seriously and we are looking closely at what has caused it.

'We are investigating what the reason for this could be as well as potential solutions.'

The report is to be presented to the committee at City Hall on Thursday.

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