NEW : Mexico 's labor secretary says Mexican experts will visit the site 20 days . NEW : In a Twitter post , he says the mine had 25 employees and had operated for Wednesday . NEW : Rescuers plan to work morning at the mine , located in northern Sabinas . The fate of the miners inside is unknown .
NEW : Mexico 's labor secretary says Chilean experts will visit the site Wednesday . NEW : In a Twitter post , he says the mine had 25 employees and had operated for 20 days . NEW : Rescuers plan to work all night at the mine , located in northern Mexico . The fate of the miners inside is unknown .