WASHINGTON - An independent panel on Thursday recommended sweeping changes at the Secret Service, saying the elite protective agency is "starved for leadership" and calling for an outsider as director, hundreds of new agents and officers, and a higher fence around the White House.

The panel, created in October after a series of highly publicized security failures, said the fence protecting the executive mansion should be raised at least four feet to make it less vulnerable to jumpers. Panel members were reacting to a Sept. 19 incident in which a man scaled the fence and ran far into the White House through an unlocked front door.

The four-person body also urged expanded, intensified training for agents, saying they should run crisis-response scenarios that possibly use a mock White House. The report targeted the Secret Service's highly insular culture, calling for new leadership from outside.

"The problems exposed by recent events go deeper than a new fence can fix," said the report's executive summary, the only portion publicly released. "We believe that at this time in the agency's history, the need for Service experience is outweighed by what the Service needs today: dynamic leadership that can move the Service forward into a new era and drive change in the organization."

The sharply worded document comes after a cascade of problems, including the agency's fumbling response in 2011 when a man fired a semiautomatic rifle at the White House residence.

Director Julia Pierson was called to Capitol Hill to answer questions about what some lawmakers called the "Keystone Cops" failures of the once highly regarded agency.

Director's resignation

Pierson resigned the following day, amid reports of yet another major security lapse - an armed private security guard who was allowed onto an elevator with President Obama in September.

Joseph Clancy, the former head of Obama's security detail, was called back out of retirement to be interim director.

The report will surely not be the final word. A House committee will launch a broader, bipartisan investigation into the Secret Service's operations in the coming year, and there is widespread debate in Congress over whether the Department of Homeland Security has provided proper leadership of the agency, which was placed inside the department after the 9/11 attacks.

"A serious and robust investigation must include cooperation on both sides of aisle in order to root out systemic problems and implement proper reforms," Reps. Jason Chaffetz (R., Utah) and Elijah Cummings (D., Md.) said of the House Oversight and Government Reform Committee probe they are planning to launch.

'No room for mistakes'

"Every day honorable men and women put their lives on the line to protect the president, first family, and others within the administration. There's no room for mistakes," Chaffetz and Cummings added in an unusual joint statement. They said their investigation "will examine security breaches . . . as well as focus on overall leadership, staffing, culture, protocol, technology, tactics and training issues."

It also remains unclear how many of the reforms suggested Thursday will be implemented. Homeland Security Secretary Jeh Johnson, who created the body, said they will be "carefully considered" and that many of the panel's security recommendations cannot be publicly released.

Praise for panel

"The panel's recommendations are astute, thorough and fair" Johnson said in a statement. "In fact, some of the panel's recommendations are similar to others made in past agency reviews, many of which were never implemented. This time must be different."

"The Secret Service itself must commit to change," added Johnson, who vowed the Homeland Security would closely monitor the agency.

The panel was composed of two former Obama administration officials - former associate attorney general Tom Perrelli and cabinet secretary Danielle Gray - and two who served under President George W. Bush - Mark Filip, a former deputy attorney general, and Joseph Hagin, a former deputy chief of staff for operations.