The latest report from the Special Inspector General for Afghanistan Reconstruction (SIGAR) paints a grim picture of the security situation in the war-torn country, and comes even as the US military asserts that Afghan troops and US-led NATO forces are seeing progress in the grueling, 16.5-year-old conflict.

It also comes on the heels of another deadly day in the capital, when twin blasts killed at least 25 people, including Agence France-Presse chief photographer for Afghanistan Shah Marai and eight other journalists.

According to SIGAR, the strength of the Afghan security forces dropped by about 10 percent over the course of a year -- falling to a total size of 296,409 personnel in the army and police forces as of January 31.

Militants including the Taliban and the Islamic State group have stepped up their attacks on beleaguered Afghan troops and police in recent months, sapping morale already hit by desertions and corruption.

When asked about the issue, US Defense Secretary Jim Mattis said that Afghan forces are actually being bolstered in the most important area -- special operations forces.

"The Afghan military is being made more capable," he told Pentagon reporters.

"You'll notice that more of the forces are special forces, advised and assisted, accompanied by NATO mentors and these are the most effective forces."

He added that this expansion was why the Taliban had not taken any district centers or provincial centers.

- Population centers -

US forces used to provide SIGAR with the number of Afghan troops being killed -- the figures were more than 5,000 each year -- but that information is now classified at the request of the Afghan government.

At the same time, the Taliban and other insurgent groups now control or influence 14.5 percent of Afghanistan's 407 districts -- the highest level since SIGAR started recording such data in late 2015.

This is "only a slight increase from last quarter, but a more than three percentage-point increase from the same period in 2016," the report notes.

The government, meanwhile, controls 56.3 percent of the districts, with the remainder considered "contested."

The varying population sizes of each district means that since August 2016, Afghan government control over its people has decreased.

"The overall trend for the insurgency is rising control over the population (from nine percent in August 2016 to 12 percent in January 2018)," the SIGAR report states.

"The Afghan government's control of districts is at its second lowest level, and the insurgency's at its highest level, since SIGAR began receiving district control data in November 2015," it adds.

The document also found increasing numbers of civilian deaths as the Afghan air force has stepped up its operations while NATO has reduced its air strikes.

The facts on the ground paint a different narrative than the one pushed by the Pentagon, which insists the Taliban are weary and now have elements willing to negotiate for peace.

Ten journalists were among dozens killed in multiple attacks across Afghanistan on Monday, in the deadliest day for the country's media since 2001.

Two suicide blasts in Kabul killed 25 people including AFP's Marai along with at least eight other journalists, in what Reporters Without Borders said was the most lethal single attack on the media since the fall of the Taliban.

The attack was claimed by IS, which has established a footprint in Afghanistan, especially in Nangarhar.

A BBC reporter was killed in a separate attack in eastern Khost province.

"The murder of journalists and other innocent people is a great testimony to what it is we stand for -- and more importantly what we stand against," Mattis said.

"We'll stand by the Afghan people, we'll stand by the Afghan government and the NATO mission will continue as we drive them to a political settlement," he added.