US investors have been increasing their stake in Powerscreen International, the Northern Ireland-based engineer, taking advantage of the sharp price fall in the wake of accounting problems. Powerscreen said that Capital Group, a US fund manager, holds 7.15 per cent of the company, up from 6.5 per cent announced on February 4th and 6 per cent in October.

Yesterday's announcement follows a statement last week that Fidelity International, another US institution, holds 4.02 per cent. It had not previously held a notifiable stake.

The announcement also said Janus Capital Corporation, an investment adviser to mutual funds in the US, holds 5.16 per cent. That is a slight fall on Janus's holding in December of 5.8 per cent. But the firm appears to have been buying shares steadily since June, when it first announced a notifiable interest of 3.15 per cent.

The recent buying by US institutions has exploited a fall in the share price following the recent announcement of a £47 million write-off relating to problems at its Matbro subsidiary.