WASHINGTON – Long-term U.S. mortgage rates rose for the second straight week, continuing to dampen prospects for potential homebuyers.

Mortgage buyer Freddie Mac says the average rate on 30-year, fixed-rate mortgages jumped to 4.60 percent this week from 4.54 percent last week. Long-term loan rates have been running at their highest levels in seven years. The average benchmark 30-year rate reached a high this year of 4.66 percent on May 24. By contrast, the rate stood at 3.93 percent a year ago.

The average rate on 15-year, fixed-rate loans increased to 4.08 percent this week from 4.02 percent last week.