Pentax K-5 DSLRPentax Japan has confirmed that its factory has launched an urgent investigation into a report that ?foreign matter? has led to ?dirty? imaging sensors on its K-5 DSLR.

Amateur Photographer was contacted by a photographer from Norwich who said he is worried having bought a K-5 earlier this month.

He said he believes that ?foreign matter’ lies under the AA filter and ?cannot be cleaned off?.

In response a spokesman for the factory told us: ?A report concerning contamination on a K-5 sensor has been brought to our attention.

?We are investigating this as a matter of urgency.?