Mining giant Bumi was leading the fallers after it said it was investigating allegations of financial and other irregularities at its Indonesian operations. The investigation centres on PT Bumi Resources, in which the company has a 29% interest, with particular focus on that firm's development funds. "The extensive development funds in PT Bumi Resources Tbk and the one development asset in PT Berau Coal Energy Tbk were marked down to zero in the accounts of Bumi plc as at December 31st 2011, except for one investment with a carrying value of $39m in the consolidated financial statements," the statement said. Petra Diamonds is in discussions with banks regarding its longer term debt requirements, and today reported that the review is "progressing well" and that banks have given "provisional commitments" subject to legal documentation and due diligence with signed documentation expected in the next three months. However, analysts at Panmure Gordon have pointed out that: "In the absence of a binding commitment from the banks, we continue to see funding as a significant risk for Petra which is one of the key reasons for our negative stance on the stock." Dairy Crest rose despite warning of lower first half profits, as challenging conditions continue, but said profit expectations for the full year ending March 31st 2013 remain unchanged. Profit before tax and exceptional items slipped to £14.9m in the six months ended July 28th, from £16.2m in the corresponding period of last year at Irn-Bru maker AG Barr. The company took a £1m hit from adverse currency movements, although around £0.6m of this is expected to unwind in the second half of the year. On a constant currency basis, first half profit before tax was £0.3m behind the similar period in the prior year. Sales in the first seven weeks of the second half have shown double digit percentage growth. Defence firm QinetiQ Group's trading has been going great guns, with first half performance stronger than originally expected, prompting shares to jump. The first half of the group's financial year saw it deliver the majority of two key orders for the Q-Net vehicle survivability product earlier than originally planned. This, together with a higher level of spares sales, more than compensated for lower sales in other major products, the company revealed.FTSE 250 - RisersPetra Diamonds Ltd.(DI) (PDL) 116.50p +6.20%QinetiQ Group (QQ.) 179.80p +4.66%Computacenter (CCC) 379.00p +3.21%Pace (PIC) 170.00p +2.87%SIG (SHI) 104.90p +2.24%Savills (SVS) 408.30p +2.08%Shanks Group (SKS) 90.35p +1.98%Brown (N.) Group (BWNG) 271.50p +1.53%PayPoint (PAY) 735.00p +1.31%RPS Group (RPS) 249.40p +1.26%FTSE 250 - FallersBumi (BUMI) 147.00p -24.96%Talvivaara Mining Company (TALV) 154.80p -5.95%Petropavlovsk (POG) 422.00p -4.00%Ferrexpo (FXPO) 207.20p -3.85%Imagination Technologies Group (IMG) 513.00p -3.48%Centamin (DI) (CEY) 92.45p -3.40%Halfords Group (HFD) 261.20p -2.83%Dunelm Group (DNLM) 666.00p -2.77%Yule Catto & Co (YULC) 167.10p -2.62%Travis Perkins (TPK) 1,057.00p -2.58%NR