Protection One Inc. announced Tuesday that it had redeemed $4.4 million in preferred stock from a European telematics company, helping trim $15 million in debt from its own balance sheet.

Protection One, a Lawrence-based provider of monitored-security services, now has $345 million in debt outstanding, the company said.

Protection One received the ATX Technologies Inc. stock when it sold its own mobile services/telematics division to ATX in 1999.

The redemption, coupled with available cash, helped Protection One continue a debt-cutting campaign, said Richard Ginsburg, Protection One’s president and chief executive officer.

“It’s a step in the right direction,” he said.

Protection One started the year $550 million in debt, but an April refinancing trimmed the total to $360 million.