TORONTO — The chief executive of struggling BlackBerry-maker Research in Motion apologized Friday after an outage in Europe and Africa interrupted service for customers on the very day Apple Inc. released its new iPhone 5.

BlackBerry announced the issues in postings on Facebook and Twitter on Friday, and later said it resolved the issue. The service disruption lasted up to three hours for some BlackBerry users in those regions.

The outage brought up unpleasant memories of last year's troubles with emails and chat messages that left many users bereft for up to three days.

The timing could not have been worse, coming as lines formed outside of Apple stores in a number of cities as the new iPhone 5 went on sale.

RIM shares plunged 6.5 percent, or 45 cents, to $6.45 in early afternoon trading on the Nasdaq.

Chief Executive Thorsten Heins said up to six percent of RIM's users may have been affected. He said the company is conducting a full analysis and will report back. No reason for the outage was given.

"I want to apologize to those BlackBerry customers in Europe and Africa who experienced an impact in their quality of service earlier this morning. The BlackBerry service is now fully restored and I can report that no data or messages were lost," Heins said in a statement posted on RIM's website.

"Preliminary analysis suggests that those customers may have experienced a maximum delay of 3 hours in the delivery and reception of their messages."