Luton have made their ninth summer signing following the arrival of winger Danny Green.
Notts County have signed Togo international Mawouna Amevor on a two-year deal.
The Hearts board has stated it has no information that Vladimir Romanov has relinquished control of the club amid further problems with his business affairs in Lithuania.
It emerged on Monday that Romanov had resigned from the board of UBIG, the company which holds a majority stake in Hearts, following the collapse of Ukio Bankas.
But Hearts director Sergejus Fedotovas, who also quit the UBIG board, indicated that Romanov, who is not a Hearts director, was still in control.
However, his attempted assurances about the club's financial security are unlikely to prevent Hearts supporters from worrying about the immediate prospects for their club, which staved off a winding-up order in December after supporters raised more than £1milion to help pay off tax debts.
In a statement on the Hearts website, Fedotovas said: "Despite recent changes to the board at UBIG, the board structure at Heart of Midlothian remains unchanged.
"The information that Mr Vladimir Romanov has relinquished his control of Hearts is pure speculation and we do not have any information to that effect.
"Changes at UBIG board do not reflect any changes in the holding structure of Mr Romanov's ownership.
"I would like to reassure supporters of the club that the board of Hearts' focus is entirely on this club and continuing the work that has allowed us to be within touching distance of having a self-sustainable business.
"This then allows us to truly develop the club both on and off the field in the seasons ahead. It is a work in progress at the moment but we are satisfied with the progress being made.
"It is also right to acknowledge that one of the principle reasons for us being unaffected at this stage by events in Lithuania is the excellent support that the fans and staff have provided to the club.
"With this continued support and ongoing diligence by the club's board of directors we believe that there is no threat to Hearts."
But confusion still surrounds the effects of the problems at Ukio Bankas and now UBIG.
Although Hearts have been running for some time without external funding from UBIG, most of their circa £24million debt lies with the investment group.
And there are fears about the future of Tynecastle after Ukio Bankas, which was majority-owned by Romanov, was declared insolvent with its valuable assets now in the hands of another Lithuanian bank. The Tynecastle floating charge is said to be held by Ukio and administrators could theoretically look to use that to raise money for creditors.
Hearts announced a £500,000 profit in May last year for the most recent financial year, but declared they were facing a £2million annual shortfall after being hit with a winding-up order by Her Majesty's Revenue and Customs in November.
A £450,000 bill was paid off while Hearts agreed to settle a separate demand by paying £1.5million over three years.
The sale of Ryan McGowan in January, the money raised by fans and their run to the Scottish Communities League Cup final could help see them through to the end of the season but the medium-term future remains unclear.
Romanov, who reportedly declared himself to be personally without cash last week, has been trying to sell the club without success for several years although takeover talks have been held in recent months.
The team are in the bottom half of the Clydesdale Bank Premier League and without a manager following the departure of John McGlynn last week.