The number of women and children seeking help at shelters for victims of violence has surged by more than 80% in Mexico under the coronavirus lockdown, according to the country's largest network of shelters for victims of violence.

The National Network of Shelters, which includes about 69 refuges across Mexico, also said the number of calls and texts it had received about family or gender-based violence had risen by 55% between March and June compared to a year ago.

"Women in Mexico are facing two pandemics: COVID-19 and family violence," the group said in a statement.

Mexico, which has been gradually easing a nationwide lockdown that began at the end of March, confirmed this week that more than 40,000 people had died of the coronavirus, among the highest death tolls in the world.

With families stuck at home under official lockdowns for months to halt the spread of the virus, tensions over household chores coupled with economic fears after nationwide job losses are more likely to escalate into violence.

The constant time together makes already-aggressive men more likely to lash out, and the majority of women seeking help had already experienced some form of violence before the pandemic, said Wendy Figueroa, head of the National Network of Shelters.

"COVID awoke situations of violence that were camouflaged, hidden," Figueroa told the Thomson Reuters Foundation. "During this lockdown, the violence gets stronger."

Attacks against women have surged across Latin America during the pandemic.

The region is home to 14 of the 25 countries with the world's highest rates of femicide - when a woman is killed because of her gender, which claims the lives of a dozen women per day in Latin America, according to the United Nations.

In Mexico, emergency calls reporting attacks on women in Mexico jumped more than 50% in the first four months of the year compared with the same period last year, government data shows.

The National Network of Shelters said overall, including by phone and social media, it had helped more than 20,000 people during the pandemic, an increase of 71% compared to the same period last year.

Nearly half the calls and messages received by the group during lockdown had come from Mexico City, which has also been among the hardest hit areas by the pandemic.

More than 500 children and adolescents received by the shelter network had been victims of sexual violence, the group said. Four out of 10 women who sought help from the group had experienced physical violence.